Cam Selection for Weber DCOE carbs

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Captainslow42
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Cam Selection for Weber DCOE carbs

Post #1 by Captainslow42 » Wed Dec 27, 2017 12:15 am

Does anyone here have experience with running 3 Weber side draft carbs on a 300? I'd be interested to know if there are any rules I ought to adhere to for selecting a cam. I have been led to understand that DCOEs perform best with high lift, moderate duration cams, with a high LSA due to reversion problems with overlap. But I'm just an amateur with an ambitious project! I'm not looking for anything too radical, as this engine is going into a car which will be frequently driven around town, and which will most likely never see a track or a drag strip, and I don't want to be stalling at stop lights and getting 5 MPG. I have been looking at a selection of comp cam and isky products, but I'm not sure where to start, so I'm open to suggestions! Thanks!

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Re: Cam Selection for Weber DCOE carbs

Post #2 by rbohm » Wed Dec 27, 2017 2:50 am

it really doesnt matter what cam you choose, so much as how you tune the carbs. reversion can be a problem with individual runner carb systems, even using holley carbs. we had the problem with pro stock cars and reversion running tunnel rams and holley dominator four barrel carbs. it usually happens though as you noted with large overlap cams, and usually at higher rpms, and even then usually in a narrow rpm band.

so pick a cam that operates in a wide rpm band, and get the tuning for your webers right, including the tuning of the air horns. as i recall, longer air horns means reversion happens at a higher rpm. its been a while since i have tuned an IR system.
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Re: Cam Selection for Weber DCOE carbs

Post #3 by Captainslow42 » Wed Dec 27, 2017 10:06 pm

Thanks for that! It's one thing in this build that I just haven't been able to get my head around. When someone says a "low" LSA I'm not quite sure what qualifies as "low" and whether or not I even need to worry about it. I'm not planning to spin this think much past 4500 rpm. Good to know! Now onto my next challenge, Getting Chokes, venturis, jets + tubes right : :)

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Re: Cam Selection for Weber DCOE carbs

Post #4 by Captainslow42 » Wed Dec 27, 2017 10:36 pm

Also, I see one of your cars is a Falcon?? I'm hoping this engine will eventually find it's way under the hood of my 61 Falcon. I'm currently short on shop space though so that'll have to wait for a bit.

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Re: Cam Selection for Weber DCOE carbs

Post #5 by pmuller9 » Wed Dec 27, 2017 11:02 pm

What year engine and compression ratio?

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Re: Cam Selection for Weber DCOE carbs

Post #6 by Captainslow42 » Wed Dec 27, 2017 11:13 pm

pmuller9 wrote:What year engine and compression ratio?



Came out of an 83 F150. Pretty sure its got the 8:1 compression, although I can't say with 100% certainty.

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Re: Cam Selection for Weber DCOE carbs

Post #7 by pmuller9 » Thu Dec 28, 2017 3:05 pm

Are you rebuilding the engine or just adding the carbs, cam and headers?

I looked at a set of these 3 weeks ago at the PRI trade show.
https://store.jenvey.co.uk/throttle-bod ... e-tdt40-48

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Re: Cam Selection for Weber DCOE carbs

Post #8 by Captainslow42 » Thu Dec 28, 2017 6:44 pm

pmuller9 wrote:Are you rebuilding the engine or just adding the carbs, cam and headers?

I looked at a set of these 3 weeks ago at the PRI trade show.
https://store.jenvey.co.uk/throttle-bod ... e-tdt40-48



I'll be doing a total rebuild top to bottom, Hyper pistons, overbore only if I need it, Cam, port and polish, 3 angle valve job, new intake, 2 into 3 exhaust headers, yet to be determined ignition mods, etc. And I'm still not sure what sort of condition the crank is in. I am mostly still in the saving and planning phase, I hope to start building in spring.

Wow, did you have something in mind for those injector units?

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Re: Cam Selection for Weber DCOE carbs

Post #9 by pmuller9 » Thu Dec 28, 2017 9:11 pm

Looks like a good plan.
The 4 highest compression Hyper pistons are:

5/64 x 5/64 x 3/16 piston ring set:
Speed Pro/Sealed power H519P
KB/Silvolite 1186H

2mm x 2mm x 4mm piston ring set:
Speed Pro/Sealed power H674P
KB/Silvolite 3171H

All have a 22cc "D" dish.
The metric ring set has less cylinder drag.

If you machine the block for Zero piston to deck clearance the compression ratio will be 8.8:1

I'm sure your build plan included screw in studs for the rocker arms which will let you use roller rockers that will easily accommodate valve lifts around .500" lift or more.

A cam with 0 +/- 1 degrees of overlap based on the .050" cam duration using the stock 110* LSA will give you a very slight lope at idle but deliver reasonable fuel mileage and plenty of power.
Here are three examples:

Crower Cams 284HDP (19205) .509”/.517” 220/222 284/290 110deg
Howards Cams 280996-10 .501”/.501” 221/221 275/275 110deg
Schneider Cams 140H (13912) .496”/.496” 220/220 280/280 110deg

With only an 8.8 compression ratio you can afford to raise the Dynamic compression ratio by using less advertised duration while decreasing the advertised duration overlap as well.
That would be the Howards cam with 275* of advertised duration
If the compression ratio was higher then the Schneider or Crower would be the better choice.

Nothing from Crane, Comp, Clifford or Isky matches.

I like to stay with a 1.6 ratio rocker arm.
The higher ratio arms increase the pressure on the lifter to cam lobe contact surface which increases the chance of losing a cam lobe.
I also prefer steel rocker arm over aluminum for longevity.
This is the last set of roller rockers I used on a build.
https://www.summitracing.com/parts/cca-1826-12
https://www.dropbox.com/s/dlwsfdl82ziie ... 4.JPG?dl=0

I was looking at Jenvey's line of throttle bodies with the hopes of finding an easy way to make Stack Injection for EFI gas street and mechanical alcohol for track use.
After looking at what most of the injection companies have to offer I'm pretty much settled on making the units myself as a single throttle body unit with six butterflies on a common shaft.

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Re: Cam Selection for Weber DCOE carbs

Post #10 by Captainslow42 » Fri Dec 29, 2017 11:56 pm

pmuller9 wrote:Looks like a good plan.
The 4 highest compression Hyper pistons are:

5/64 x 5/64 x 3/16 piston ring set:
Speed Pro/Sealed power H519P
KB/Silvolite 1186H

2mm x 2mm x 4mm piston ring set:
Speed Pro/Sealed power H674P
KB/Silvolite 3171H

All have a 22cc "D" dish.
The metric ring set has less cylinder drag.

If you machine the block for Zero piston to deck clearance the compression ratio will be 8.8:1

I'm sure your build plan included screw in studs for the rocker arms which will let you use roller rockers that will easily accommodate valve lifts around .500" lift or more.

A cam with 0 +/- 1 degrees of overlap based on the .050" cam duration using the stock 110* LSA will give you a very slight lope at idle but deliver reasonable fuel mileage and plenty of power.
Here are three examples:

Crower Cams 284HDP (19205) .509”/.517” 220/222 284/290 110deg
Howards Cams 280996-10 .501”/.501” 221/221 275/275 110deg
Schneider Cams 140H (13912) .496”/.496” 220/220 280/280 110deg

With only an 8.8 compression ratio you can afford to raise the Dynamic compression ratio by using less advertised duration while decreasing the advertised duration overlap as well.
That would be the Howards cam with 275* of advertised duration
If the compression ratio was higher then the Schneider or Crower would be the better choice.

Nothing from Crane, Comp, Clifford or Isky matches.

I like to stay with a 1.6 ratio rocker arm.
The higher ratio arms increase the pressure on the lifter to cam lobe contact surface which increases the chance of losing a cam lobe.
I also prefer steel rocker arm over aluminum for longevity.
This is the last set of roller rockers I used on a build.
https://www.summitracing.com/parts/cca-1826-12
https://www.dropbox.com/s/dlwsfdl82ziie ... 4.JPG?dl=0

I was looking at Jenvey's line of throttle bodies with the hopes of finding an easy way to make Stack Injection for EFI gas street and mechanical alcohol for track use.
After looking at what most of the injection companies have to offer I'm pretty much settled on making the units myself as a single throttle body unit with six butterflies on a common shaft.



Wow! Thanks pmuller9 for all your help :) I've got a lot of thinking to do now. Are the screw in studs something which is available specifically as an upgrade for the 300 head or are they sourced from a different engine? I've been looking all over for them online and can't seem to find exactly the set I need...Also, would you recommend going to a 7/16" stud? thanks again!

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Re: Cam Selection for Weber DCOE carbs

Post #11 by pmuller9 » Sat Dec 30, 2017 2:00 pm

There aren't any rocker studs that are specific for the Ford 300.
If you use the 1.6 Ratio BBC rockers I recommeded then you will need a 7/16" upper end.
I used a 1.75" long rocker stud.

Are you looking at larger intake and exhaust valves?
The 1.910" long SBC 1.94" intake and 1.60" exhaust valve work well.
The non-EFI heads has 1.810" long valve.
All stock valves are 1.780" intake diameter and 1.559" exhaust diameter.

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Re: Cam Selection for Weber DCOE carbs

Post #12 by Captainslow42 » Sat Dec 30, 2017 11:40 pm

pmuller9 wrote:Are you looking at larger intake and exhaust valves?
The 1.910" long SBC 1.94" intake and 1.60" exhaust valve work well.
The non-EFI heads has 1.810" long valve.
All stock valves are 1.780" intake diameter and 1.559" exhaust diameter.


I had thought about the larger valves, I was unsure of the cost of milling the head to accept the new valve seats, and I haven't got pricing from anyone in my area. I would if I could do it without breaking the bank. Although I guess it would be pointless to send the head off to a shop to get New stock valves and seats installed and modified, stick the thing back together, drive for a few months then pull it apart and move to enlarged valves, might as well just do it. Will I need a matched set of pushrods with the taller bbc valves? Valve train geometry is a subject I am not well schooled in...

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Re: Cam Selection for Weber DCOE carbs

Post #13 by pmuller9 » Sat Dec 30, 2017 11:50 pm

Captainslow42 wrote: Will I need a matched set of pushrods with the taller bbc valves? Valve train geometry is a subject I am not well schooled in...

SBC valves

I needed longer pushrods for my set-up.
The roller rocker tip needs to ride across the center of the valve stem tip.

In theory at mid valve lift, the line through the center of the roller rocker tip and the center of the roller rocker shaft or pivot point should be 90 degrees with the valve stem.

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Re: Cam Selection for Weber DCOE carbs

Post #14 by WorldChampGramp » Sun Dec 31, 2017 10:27 am

It is so refreshing to see all this knowledge shared openly among likeminded inline Ford enthusiasts. EVERYONE on this Forum should be thankful to those contributors like P. Muller who in my opinion is one of the most knowledgeable engine builders I have ever had the privilege to converse with. Now To the point. I vividly recall some 45 years ago when we went through the rocker arm geometry issues with Preparation H. Using an adjustable pushrod available for many sources like Summit, Comp cams etc. the near perfect length can be determined using a black Magic Marker or machinist’s layout dye on the tip of the intake/exhaust valve stem. With adequate spring tension [even with a lighter ‘checking spring’] the roller rocker will clearly show you just where the center of its force is on the valve stem tip. Too short a pushrod will make an impression to far toward the “toe” of the valve toward the spark plug side of the head. The reverse is true of a too long pushrod. Order your custom 3/8’ pushrods based on the above SUGGESTION and you “should be good to Go” pun intended. Just my 2-cents Bruce Sizemore

:beer: HAPPY NEW YEAR To All

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Re: Cam Selection for Weber DCOE carbs

Post #15 by Captainslow42 » Sun Dec 31, 2017 6:41 pm

Thankyou all for taking the time to share your expertise with me! I've got so many more questions floating around in my head, but what I really need to do next is get the thing on a stand and start tearing it down and cleaning/measuring everything so I know exactly what I've all got! Hopefully 2018 is going to be a busy year :D

Happy New Years!!

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Re: Cam Selection for Weber DCOE carbs

Post #16 by pmuller9 » Sun Dec 31, 2017 8:56 pm

What size are your Weber DCOE carbs?

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Re: Cam Selection for Weber DCOE carbs

Post #17 by Captainslow42 » Sun Dec 31, 2017 9:35 pm

pmuller9 wrote:What size are your Weber DCOE carbs?



I selected 45's, the 152 model

Main Venturi - 36mm

Aux Venturi - 45

Air ram tube- 62mm length

Main Jet - 145

Air corrector - 155

Emulsion tube - F18

Idle Jet - 55 F8

Accelerator pump Jet- 45

Accelerator pump valve - 40

Start Jet - 85 F9

Start Jet air corrector - 150

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Re: Cam Selection for Weber DCOE carbs

Post #18 by Captainslow42 » Sat Jan 06, 2018 12:54 pm

I've also been brushing up on some of the theory behind intake tuning in preparation for choosing parts, and I've been left a little bit uncertain about a few things. Is it possible to port out a 300 head too much? I don't know how much I would need to open it up before I would begin to see a detrimental loss in intake air velocity. The IR intake I plan on using has fairly long runners, and I don't want to disrupt the "intake ramming" this gives me at low/mid rpm by creating a large pressure drop right before the valve. Or is the stock head so restrictive that I can safely enlarge the ports and valves without much concern? Any advice would be appreciated :)

Another thing I've been wondering about is fuel atomization. I was talking to the manufacturer of this particular manifold (guess who :) ) and was told that one of the reasons production was originally discontinued was because of poor fuel atomization in the runners. I've also been led to believe that one downside of polishing intakes and heads is that while it improves total air flow volume, the elimination of the rough casting surface also eliminates the "boundary layer" airflow that normally prevents fuel from condensing and pooling in the walls of the intake runner. Is this anything I need to be concerned about? Again, I may be a little out of my depth here :? If anyone can shed some light on this for me, you have my thanks :D

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Re: Cam Selection for Weber DCOE carbs

Post #19 by pmuller9 » Sat Jan 06, 2018 1:21 pm

Even fully ported big valve 300 head ports are too small for 50 cid cylinders.
The port walls are thin and it is easy to hit water jacket so port enlargement is limited.
Most of the work is focused in the pocket area around the valve guide boss/

The Jenvey solution to the Weber atomization problem is delt with by installing fuel injectors in the body so it still looks like a Weber but has better fuel control.
https://store.jenvey.co.uk/throttle-bod ... e-tdt40-48

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Re: Cam Selection for Weber DCOE carbs

Post #20 by Captainslow42 » Wed Jan 10, 2018 11:23 pm

Thanks! I'll scale back my porting plans a bit. Rather not risk wrecking a perfectly good head if there isn't much room. Would you recommend De-shrouding the valves? If I go to the larger chevy valves will there be much room to do so anyways? I apologize if these questions have obvious answers, I haven't really had an opportunity to pull the head yet... Also, on another note, in the picture you shared with me of your roller rocker setup I noticed you installed pushrod guideplates. I had thought that guideplates were only necessary with the later pedestal-mount rockers/ efi heads? or does it have something to do with the fatter pushrods?

:thanks:

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Re: Cam Selection for Weber DCOE carbs

Post #21 by pmuller9 » Wed Jan 10, 2018 11:44 pm

The 1985 and 86 carb heads also had pedestal mount rockers. My head was an 86.
If your head is an 83 then you will not need guideplates.

I bolted the head on to the bare block and scribed the cylinder bore circle to the head surface.
Then I pulled the spark plug side of the chamber walls back to the scribe line and smoothed out the rest.
These are 2.02/1.64 SBC valves. I recommend staying with the 1.94/1.60 combination.
https://www.dropbox.com/s/5t7b6y8h5vdpu ... r.JPG?dl=0

Intake port: Notice that most of the work is in the bowl area around the valve guide. The port walls hade very little material removed.
https://www.dropbox.com/s/xklz27x77cvgh ... 3.JPG?dl=0

Exhaust port: Here the valve guide boss is ground flat across leaving a shelf before entering the port.
You can also see the undercut valve stem.
https://www.dropbox.com/s/pycdq6q58ecd0 ... t.jpg?dl=0

Ask any question you need to.

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Re: Cam Selection for Weber DCOE carbs

Post #22 by WorldChampGramp » Thu Jan 11, 2018 12:10 am

PMuller9 what bore size are the scribe lines attributed to. Bruce Opps Flight tomorrow AM better quit while I am a head. 240 rather than 300 :idea:

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Re: Cam Selection for Weber DCOE carbs

Post #23 by pmuller9 » Thu Jan 11, 2018 12:17 am

WorldChampGramp wrote:PMuller9 what bore size are the scribe lines attributed to. Bruce Opps Flight tomorrow AM better quit while I am a head. 240 rather than 300 :idea:

In this case it was 4.040"
I don't care for the 240 head, Too much shrouding with big valves.
Safe Trip.

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Re: Cam Selection for Weber DCOE carbs

Post #24 by Captainslow42 » Thu Aug 23, 2018 8:20 pm

So, I have finally been making a bit more progress these last few weeks! I received my head back from Brazier Race and Machine in Winnipeg MB, with ARP rocker studs, positive valve seals, guides and most importantly a set of new undercut Manley Valves, 1.84 on the intake and 1.60 on exhaust. I decided to stick with the slightly smaller 1.84 after the machinist voiced concerns to me about the thickness of the casting in the seat area. They left the bowl areas rough cut when I told them I wanted to do the porting/clean up work myself. I have shaped one intake and one exhaust to the point where I feel pleased with the results, but this is my first time doing any porting work and I'd really appreciate any feedback or criticisms on the work before I replicate it on subsequent cylinders.

Image Image Image

And the exhaust:

Image Image Image

I can take more pictures if these don't show enough detail.

I was probably a bit on the conservative side as far as removing material from the valve guide boss, partially because I didn't want to risk wrecking a head I had already sunk $$$ into, I'm holding off on doing the rest, hoping to get a few words from our resident experts before proceeding. Next time around, I'll practice on a scrap head first...

Image Image


While the head was at the shop, we discussed the valvetrain components I was intending to use. They ordered in a kit from Howards Cams which contained the 280996-10 camshaft previously recommended to me by pmuller, a set of lifters and the recommended set of valve springs. But I've got a bit of a dilemma. I notice that according to the Howards website, this Cam "Needs good exhaust". I'm not entirely sure what qualifies as "good exhaust". I have been going back and forth in my mind between a set of headers and a set of EFI manifolds with duals to the rear. With headers I am concerned about underhood heat, clearance in and under my falcons engine bay, and finding a set for a decent price. I like the performance potential and sound of the headers, and I assume that they will flow better than the EFI manifolds. But I like the price tag and thermal properties of the efi manifolds. I can get them for about the price of shipping on a set of mid-length headers. Would the EFI manifolds qualify as "Good exhaust"? I don't want to compromise the work done on the head and the benefits of the new cam, so the headers are definitely still on the table. Thoughts? your advice and input is appreciated!
Last edited by Captainslow42 on Sat Aug 25, 2018 10:01 pm, edited 2 times in total.

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Re: Cam Selection for Weber DCOE carbs

Post #25 by pmuller9 » Thu Aug 23, 2018 10:26 pm

Good exhaust means Not the log exhaust manifold.

The EFI exhaust manifolds will work fine.
The more power the engine makes the greater difference the header makes over the EFI exhaust manifolds.
Last edited by pmuller9 on Fri Aug 24, 2018 12:36 am, edited 1 time in total.

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Re: Cam Selection for Weber DCOE carbs

Post #26 by THE FRENCHTOWN FLYER » Thu Aug 23, 2018 10:59 pm

I think you did a very good job especially for a newb. Staying a little on the conservative side will insure better longevity (I've got a pile of cracked ones from going a little too far).

PS: I also ran a Falcon Sprint with a 240 / toploader / 9 incher. Had a ball with that car. It was my first big six build up. What fun. Ran low 13s. Had a total of $900 invested.

Image
FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

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Re: Cam Selection for Weber DCOE carbs

Post #27 by pmuller9 » Thu Aug 23, 2018 11:14 pm

In the Howard catalog, the 280996-10 cam is specified to use the 98411 valve springs.
At an installed height of 1.700" it will have a seat pressure of 90 lbs which is only 10 lbs more than stock. Not a big deal.

But it has a spring rate of 210 lbs/in where the stock spring is 293 lbs/in.
I would expect valve float before the engine gets to the top of it's power band.

I would prefer the 98412 spring which has a 1.700" seat pressure of 110 and a spring rate of 350.

I edited my previous statement on exhaust port modifications and am in agreement with FTF on staying conservative.
What you have is well done.

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Re: Cam Selection for Weber DCOE carbs

Post #28 by Captainslow42 » Sat Aug 25, 2018 3:28 pm

THE FRENCHTOWN FLYER wrote:I think you did a very good job especially for a newb. Staying a little on the conservative side will insure better longevity (I've got a pile of cracked ones from going a little too far).

PS: I also ran a Falcon Sprint with a 240 / toploader / 9 incher. Had a ball with that car. It was my first big six build up. What fun. Ran low 13s. Had a total of $900 invested.

Image


Thankyou! I appreciate the compliment, I'll probably get to work on the rest some time this afternoon, if I can find the time... If I may ask, did you have a huge amount of difficulty shoehorning that 240 in to your Falcon lengthwise? Mine is a 61, which will have a whole new front end without shock towers so I don't anticipate any problems width wise. Did you need to modify the firewall or run a different fan setup to make it fit?

Thanks again!

Image

Jesse


pmuller9 wrote:In the Howard catalog, the 280996-10 cam is specified to use the 98411 valve springs.
At an installed height of 1.700" it will have a seat pressure of 90 lbs which is only 10 lbs more than stock. Not a big deal.

But it has a spring rate of 210 lbs/in where the stock spring is 293 lbs/in.
I would expect valve float before the engine gets to the top of it's power band.

I would prefer the 98412 spring which has a 1.700" seat pressure of 110 and a spring rate of 350.

I edited my previous statement on exhaust port modifications and am in agreement with FTF on staying conservative.
What you have is well done.


When the machine work was done on the head, and the cam and lifters were ordered, I asked for the set of recommended valve springs. Perhaps I got the engine builders recommendations rather than the manufacturers? I was given a box containing 12 of these:

Image

http://www.straubtechnologies.com/110-1 ... 1-260-870/

http://online.flipbuilder.com/dgew/roam/index.html#p=14

The springs have an installed height of 1.875 inches on my head and an uncompressed height of 2.125 inches. The calculations I did using these numbers yield me approximately 100lbs on the seat and 300 @ .501 at the 400lbs/inch spring rate. Does that sound right to you? I tried it another way, using the given seat pressure of 130lbs @ an installed height of 1.75 subtracting the difference between this and my installed height (.125) multiplying it by the spring rate and subtracting it from the 130. ending up with only 80lbs seat pressure. I'm a bit confused, the figure of 130lbs doesnt seem to add up in my mind but it's from the manufacturer and they sure know a heck of a lot more than I do about valve springs :p

Also, do you think these springs are a bit on the heavy side for breaking in my cam? I'd hate to wipe out a lobe and need to buy a whole round of new parts!

I appreciate your responses, I'm all about learning!

Jesse

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Re: Cam Selection for Weber DCOE carbs

Post #29 by pmuller9 » Sat Aug 25, 2018 5:10 pm

If the spring pressure is 130# at 1.750" and the installed height is 1.875", that is a difference of .125"
Multiply the spring rate by the difference, 400 x .125 = 50 lbs.
130# at 1.750" - 50# = 80# @ 1.875"

Total valve lift of .500" multiplied by the spring rate = .500" x 400 = 200#
Add seat pressure to lift pressure = 80 + 200 = 280#

280 is OK for break-in if you use the correct break-in oil

What length valves are you using?

There is a problem I need you to look at.
The ID of the 110-1574 spring is .870"
The OD of the spring locator on the head is 1.00"
How did you make the spring sit around the locator or is it sitting on top of the locator?

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Re: Cam Selection for Weber DCOE carbs

Post #30 by Captainslow42 » Sat Aug 25, 2018 6:10 pm

Image

It seems that when the cuts were made for the positive seals, the locator was also turned down to .75", but I'm not sure exactly why. Should I have a locator seat/cup underneath with the appropriate dimensions? I currently have the spring just sitting down on the head. I guess it didn't occur to me that this was a problem because I hadn't removed any such locator cups when I removed the old springs, that makes sense...

The valves I have are 4.911

https://www.jegs.com/i/Manley/660/11506-1/10002/-1

https://www.jegs.com/i/Manley/660/10549-1/10002/-1

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Re: Cam Selection for Weber DCOE carbs

Post #31 by pmuller9 » Sat Aug 25, 2018 8:00 pm

Turning the stock locator down to .750" is fine to locate the springs you are using.
I just wanted to make sure the springs were sitting on the head surface and not on top of the stock 1.00" locator.
You are good to go.
Looks like you are working with a good machine shop.

Are you using the 100-1257 or 100-1258 retainers?

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Re: Cam Selection for Weber DCOE carbs

Post #32 by xctasy » Sat Aug 25, 2018 9:37 pm

Captainslow42 wrote:Does anyone here have experience with running 3 Weber side draft carbs on a 300? I'd be interested to know if there are any rules I ought to adhere to for selecting a cam. I have been led to understand that DCOEs perform best with high lift, moderate duration cams, with a high LSA due to reversion problems with overlap. But I'm just an amateur with an ambitious project! I'm not looking for anything too radical, as this engine is going into a car which will be frequently driven around town, and which will most likely never see a track or a drag strip, and I don't want to be stalling at stop lights and getting 5 MPG. I have been looking at a selection of comp cam and isky products, but I'm not sure where to start, so I'm open to suggestions! Thanks!





The correct size for matching the carb venturi size to the engine is Eduardo Webers ventiri to rev range graph.36 mm is way too small. Another guy here is doing a 300 Ford engined TR4 Triumph, and has sadly decided to use 36 mm venturis, which restricts a 300 Ford with an isoltaed runner to about 3600 rpm for its peak power rpm, so it cannot make more than about 207 hp at 3600 rpm. The engine with the right cam and venturis could make over 295 hp at 4400 rpm or so. IR systems despise small venturi area, and the bigger the engine, the more it is restricted by small venturi sizes.



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It requires very large venturis to match the engine rpm.

For a 300 cube engine in the 3600 to 5500 rpm power ranges, you have to back re-calculate using the following chart.


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Since one cylinder is 819 cc's, the chart goes off the scale too early. Former ford six meber panic quoted the size for going off the scale at 45 cubic inches per cylinder or 737 cc per cylinder with one 45 mm venturi 48 IDA Weber. Enough for a 270 cubic inch engine with power to 6000 rpm.

Thats a 1.77 inch venturi.


Bascially, as panic (from the Jeremy Diamond Victory Libary) found, http://victorylibrary.com/mopar/intake-tech-c.htm


Type 3:

The Isolated Runner manifold is not standard equipment on any domestic V8, but common on earlier high- performance 4, 6, 8 and 12 cylinder imports and racing Cobras (289 & 427), typically using dual-throat Weber, Dell’Orto, Solex or Mikuni PHH carburetors. These are not true manifolds, as their only function is to connect 1 intake port to 1 throttle disc or slide. There is no commonality or sharing (except for a vacuum balance hose or passage for idle quality).
IR manifolds, where each cylinder can only draw from one barrel, offer the absolute best idle quality, throttle response, tolerance of high-overlap cams timing, and allow accurate tuning of intake length for maximum torque. The disadvantages are higher mechanical complexity, synchronization problems, limited under-hood space for intake stacks, and much higher manufacturing costs.
Even using the largest common IR carburetors (Weber 48mm IDA with 45mm venturis) the maximum cylinder size is about 45” (or 70 HP, whichever is less). The Weber flows about 330 CFM per barrel, giving a total of 2600 CFM, but this is barely enough to supply a 360” motor @ 7000 RPM. This is why IR manifolds have not been that successful in drag racing - even 2 Dominators aren’t enough to supply a 500” motor (62.5” cylinders) @ 10,000 RPM without some plenum to allow partial supply from other barrels. Completely separated IR carburetors for this motor would require 63mm (2.47”) venturis!
Larger motors will develop less power than with conventional tunnel-ram set-ups, due to inadequate flow capacity - each cylinder only “sees” 1 throat or barrel. There is no carburetor currently available large enough for 1 barrel to supply enough air for a 70” cylinder.
There have been IR manifolds (typically using 4 dual-throat Weber 48 IDA down-draft or DCOE side-draft carburetors) available for some V8 motors, especially Ford Windsor and FE, and small & big block Chevrolet.



as you go up in cylinder capacity for Independent Runner systems, you have to go a lot bigger in Venturi size. For 240 to 250 and 265 cubic inch in line sixes, 36, 37, 38 and 40 mm is w-a-y too small.

36 mm in a 45DCOE results in a peak rev range of about 3600 rpm, not worth the effort. Biggest you can add in a 45DCOE is a 40 mm chocke, and on a 5 liter in line six, that takes the peak rev range for power to about 4400 rpm. The maximum venturi size for DCOE's varies. On 40DCOE's, you biggest ventir size is 5 mm less than the DCOE call size. On the 45 DCOE, its 5 mm less than the call size. On the rare other versions, the 48 DCO, or 48 DHLA Dellorto, its still 5mm less than the call size.

To get the rpm at peak power to match the port area you might need a set of 55 or 58 DCO's with 44 venturis. Perperation H had the stock IDA 48 ventir sizes, and it healed over at 6500 rpm. The key is the weber charts.

See viewtopic.php?f=5&t=78236&p=604721#p604721


With respect to a 250 or 265 cubic inch engine, the ideal venturi size for a port with about 2.14 to 2.2 sq inches like a 250 2V or 265 Chrysler Hemi Six has, that only makes power at 5500 or 5300 rpm with a 40 mm 1.575" venturi. It allows over speeding to 6500 rpm, as long as the cam duration and lift cross the minimum Stan Weiss requirements to make power at 5500rpm. One of the singularly most intoxicating thing about Inependent Runner Induction is the ability to over speed past the peak power rpm.

xctasy wrote:I had a 150 word discussion with Mike W back in the mid Noughties.

I've never liked EFi becasue of the safety aspect of fuel pumps, cut off fuel supply, and having to run high pressures. The wiring to the gas tank is the biggest issue, and the feedback O2 sensors are always keyed into a air fuel map, and then you have to decide how your gonna meter it out. Bank fire, sequential, Speed Density or MAF.



The carb is much easier to use on a low pressure 7 psi situation.


I felt then that as well as the longer Cross flow head bolts, he should look at a standard Weber intake manifold, and then add a Holley to Weber DCOE 45 gooseneck to fit either one 2-bbl, two 2-bbls, or three 2bll Holley carbs. Then you would have to add a Cobra6/ Harrie style upper spring tower brace bar set like the Argentine guys do. But it looked doable back then, still does today.


Ultimately, Mike decided that the 2-bbl to 4-bbl single Holley was the best use of his resources, because most sellers split the 2V head and stock 2V intake and sell seperate to get a better sale price. Part A, goes with Part B, ya know.


Anyway, I've always thought buying two of these, and turning them up side down, and cutting them would make an awesome triple Holley 500 cfm 4412 carb adaptor to the 250 2V, Classic In lines or Vintage inlines head.



Image





The ideal carb venturi size is about 40 mm, or 1.575" for a good 295 hp net engine. The Holley 2300 series base can just be inserted to that size using a USA sourced insert kit on a PN #4412 s500 CFM 2-BBL Oor PN #6245 650 CFM 2-BBL. The old 1.33 Autolite 2100 and current Chinese 2150 Motorcraft carbs do not have the casting thickness to perform the same trick. Cutting up some old Dominator 4-bbls into some 2-bbl Split carbs will give yopu the venturi area you need. Going under six 36 mm venturis on on a four liter engine strangles the rev range past 4500 rpm. Three 4412 carbs with the 1.375" venturis taken out to 1.4375" will J-U-S-T work on a 250 six reving no more than 4800 rpm. The ports on the 2V 250, Classic Inines and Vintage In lines head are able to make power to 6000 rpm.


According to Stan Weiss et al, the heal over point where peak rpm and power are made is based on port area and valve lift, and actual CFM at that valve lift.


The question isn't what intake manifold you want, but how are you gonna get the carb venturi area.

The critical relationship between venturi size and rev range on independent runner carbs was established during World War Two by il Commendatore Edurado Weber before his untimely death. His work was with aero engines.

The ideal carb venturi was established by Aston Martin with the 4 liter DB5's, 6's and the last DBS 6 cylinder engines. Chrysler Australia used the DBS Vanatage carbs, and found them just right, as both cars made the same power....325 hp gross for the DBS Vtange 6 cylinder, and A fudged down 302 hp gross for the E49, both had the same 40 mm venturi, and the same carbs. Only the E49 was actually 295 hp net at 5600 rpm.


The 36mm venturis made only 248 hp on the E37 Valiant Pacer , and the 38 mm venturis, 280 hp on the E38 Valiant Charger. The old Renault Torino GR with triple DCOE 45's used 37 mm venturis, and only reved to 4700 rpm, if I recall right.


So it is carb size that governs horsepower and mid range torque, not intake maniolds, if all else is equal. Intake runner length isn't critical if the goose neck to the intake ports isn't too sharp. Direct mount 2-bbl carbs with some 40mm venturis on a log head will make as much power as side draft DCOE 45's on a 2V 250 head. Its venturi size, port area, cam lift, and the Weber chart takes precendece over anything else as long as the ports sizes are big enough to match the throttle blades.



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Mike W's 1969 Mustang 6i was based around this basic idea.....that an in line Ford six with Idependent Throtttle Bodies and a detachable intake would match, and infact exceed the performance of a factory 265 Hemi Six Pack.




Best non Weber choices:



I'm quite sure a routed out 2300 series carb with 650 cfm like the 1.4375" 37 mm #6245 sieries 2-BBL,

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or the brilliant, unlimited # 4412 2300 series based aftermarket 890 cfm C&S 1.56" (40 mm ) 2-bbl carbs would make the best power.

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There is even the Split Billet Dominator unlimited 2 barrel 2” with 1.69" (over 43 mm) venturi carbs for unrestricted V-8 2 barrel classes that outflows 890 cfm carb above for even more excellent power.

Image
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XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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Re: Cam Selection for Weber DCOE carbs

Post #33 by xctasy » Sun Aug 26, 2018 3:18 pm

Once you have the right venturis, you'll find a cam close to the old Ford Maverick Preperation H cam will idle nice, and make awesome power.


You have to dial in a cam duration at 50 thou lift, a cam lift at wide open, and a cam duration at lash that supports a peak power rpm of 4400 to about 5000 rpm. I seriously doubt it'll peak at 5000 rpm, but it'll cetainly rev from 4400 rpm to 5800 rpm with the utmost ease and alacrity.


Use 40 mm venturis with your 45 DCOE's , and your peak power rpm will be between 4400 andless than 5000 rpm.


The cam has to match the venturi sizes peak power rpm, and the port area has to support that rpm. Everything has to match, or it'll heal over at the wrong engine speed.






viewtopic.php?f=2&t=73522&p=604610#p604610
xctasy wrote:https://fordsix.com/viewtopic.php?f=2&t=55514&p=433836#p433836
ivonius wrote:.....Just bought a used set of Triple 45DCOE sidedrafts (36 chokes). ....


If you can find some 40 mm chokes.Are yours Model 13 45DCOE's?


Then you'll get a power peak at about 5000 rpm, and it'll make 295 hp easily (net at the flywheel).


Look up the 1972 265 Hemi Valiant Chrysler E49 Six pack carb tuning details.

145 micron jets.
https://www.weberperformance.com.au/pro ... ducts_id=5
E-49 Specifications
(40mm chokes,
4.5 aux venturi,
145 main jet,
170 air corrector,
F2 emulsion tube,
55F9 idle jet,
45 pump jet,
200 needle valve)

Our triple 45 DCOE Weber conversion to suit the 265 Hemi engine is the best quality, and best value for money kit available on the market. We supply only top quality linkage components and our own optional extras such as genuine bakelite spacers to dramatically reduce heat transfer into the carburettors. We only use the 152G model carburettor with 4 progression holes which gives a superior transition from the idle to main circuit.
Image
XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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Re: Cam Selection for Weber DCOE carbs

Post #34 by xctasy » Tue Aug 28, 2018 10:25 am

The engine needs the same sized venturis as the 48 IDA's on Bruce Sizemores (WorldChampGramp)71 Mav.

Vintage 1971 footage of Bruce Sizemore's 6 cylinder H/MP Maverick competing at St. Thomas Dragway
https://www.youtube.com/watch?v=sIiHCvg ... tion=share

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Same cam, same attention to detail.

42 mm choke venturi's really require a set of rare 48 DCOE's, but if you have to, the 45DCOE's can run 42's...just. Dellorto 48's are a great option if you can track 'em down.

A Weber 48 IDA's are downdrft carbs, and have a choke venturi a nominal 42mm ex factory, with anything from 36 to even 46 mm possiable.


viewtopic.php?t=74077
CoupeBoy wrote:This article has been on the internet for a few years in digital copy, I took a bit of time this morning and retyped the text portion. I'll see what I can do about the associated images in the new future.
Fordman75 posted the scanned article here.
Cylinder head find, bust or a treasure? -- Ford-Trucks.com
Eleven-Second Six
By Don Green

Ford's failure to release a V8 Maverick in 1971 (in a year when they approved the use of a 302-inch V8 in the new Comet, Lincoln-Mercury's version of the Maverick) was a definite cause for disappointment to small car fans. This was especially true because everyone had known since its original release hat the car was designed for a V8 (all, the necessary mounting holes were already in place on the chassis). Also, rumors had been circulating for a full year about the soon-to-be-releasedV8-powered Maverick, but 1971 announcement time came and went, and no V8 was to be had. Only the clunky standby sixes.

But apparently things weren't as bad as they seemed. Especially if you asked a group of Detroit area racers who were long-time proponents of straight sixes and eights. The group, numbering four, was in the process of preparing a six-cylinder Maveric for H/Modified Production, and a more unlikely group of guys to be racing Fords would be hard to find. Frang Prayg, an employee of General MotorsMotors Styling. Bot White, a Parts Manager at an Oldsmobile dealership. Art Keyes, a machine shop foreman; and their ace-in-the-hole. Bruce Sizemore, and employee of the Ford Motor Company, comprisedthe foursome. At that time Bruce was working in the now-defunct Performance Events group. He provided technical advice and is to a great degree, responsible for the construction of the engine.

The car is now running and running well. Driven by C/Stock record holder Tom Schumacher of Columbus Ohio, the Maverick was the H/MP class winner at the 1970 Indy Nationals. The best performance to date for the 2810-pound car is a very creditable 11.92 at 114 mph (the current National Record is 12.06 seconds). Theclass the car falls in, H/MP, understandably explains the car's name. "Preparation H", but the car's performance prevents it from being the butt of suppository-oriented jokes.

Anyone who has ever tried to make a six-cylinder engine competitive knows the myriad problems associated with an engine that was designed to be an economical workhorse rather than a racer. If nothing else, the vibration that in-line engines develop at certain rpm can frustrate and overwhelm all but the most serious engine builders. But Sizemore, Prayg, and others have been there before. They've repeatedly solved these problems on many different types of engines and were able to make the Maverick engine perform with the best with what appears to be very little effort. They were also very happy to discuss their approach to in-line engine building using their 11-second six as an example. But they were quick to stress that despite how the current engien runs, it is far from the final answer. Through their experience, they were able to develop a combination that worked well the first time.. And since the season was in progress when the car was first run, very little of the trial and error as experimenting has been done to improve the cars performance. When the racing season begins again in the Detroit-Ohio area, permitting more development work. Sizemore is confident that the Maverick will run 11.7's.

The engineis based on the 240 cubic inch six that was released in 1965 for use in the large bodied Ford passenger cars, Econolines and light trucks, and is commonly used in Taxis. With exception of the crankshaft, this engine provides all the basic raw material. The stock 3.18 inch stroke 240 crank is replaced by a heavy-duty crank from a 300 cubic inch Ford truck engine. The 300 crank, part number C5TZ-6303-D, has a 3.98-inch stroke and is made from forged steel with flame-hardened rod and main journals. There is also a 300 light-duty truck crank, but the heavy-duty version is the one to use. Bruce has the mains grooved by the Moldex Tool Company (the steel is so hard that the crank cannot be cross-drilled). Naturally, the crank should be checked for straightness. Use the 300 truck crankshaft damper, part number C5TZ-6312-K. When installing it, make sure both crankshaft snout and the inside of the dampner are perfectly clean. A particle of dirt could burr the shaft, throw the damper out of position and cause vibration. The damper should be torqued to 130-140 lbs-ft. It is also a good idea to mark the front of the damper to let you know if the outer half has slipped in relation to the inner half, as this would make your timing mark inaccurate.

The 240 engine block is a thinwall casting with a 4.00-inch bore and is identical to the 300 block. The first engine Sizemore built for the Maverick was overbored .060-inch. The large bore proved satisfactory for a couple of months of competition, but the walls of two of the cylinders finally cracked from teh strain. In the future no more than a .040-inch overbore is planned. The group align-bored the mains to insure accurate crankshaft fit. Bruce installs the crank with .003-inch clearance on the mains, using Clevite 77 bearings. The thrust is set at .006-inch. The block's deck surface should also be O-ringed using any good grade copper or stainless steel wire. The o-ring grooves should be cut with a diameter of 4.375 inches around each bore, and should allow the wire to protrude approximately .008-inch above the surface of the deck.

Sizemore uses 240 rods which are longer than those used with the 300 crank. The 240 rods have a center-to-center length of 6.79 inches, while the 300 rods are only 6.21 inches long center-to-center. The longer rods were selected to allowthe pin hole to be placed higher in the piston, hopefully reducing any possible tendacy for the pistons to rock in the bore. Naturally, the longer rods also reduce the rod angle and thrust.

The deicsion to use the longer rods was based on past experience. Also, Bruce was able to draw some parallels between the six and the successful 428's 4.13-inch bore, and both have an identical 3.98-inch stroke, so he sought a rod length comparable to that of the race-prepared 428. At this time he has not tried the stock length 300 rod for comparison.

The 240 rods were manufactured in two versions. Those made in 1969 and later have an oil squire hole drilled in a heavy boss on the rod's big end that srays oil from the crank journal toward the piston pin. Those rods prodcued in 1968 and earlier do not have the oil hole and boss and are therefore lighter. The '68 and earlier 240 rods (part number C5AZ-6200-A) also have smaller diameter, lighter wrist pins(.9121-inch compared with the '69 and later .9752-inch pins).

The rods should be prepared by grinding the forging lines from the sides of the rod's I-beam section (all grinding should be done lengthwise on the beam section) and drilling a 1/8-inch oil hole in the top of the rod to help lubricate the piston pin. The hole should be chamfered slightly after drilling. These operations hsould be followed by a complete deburring and a throough shot-peening for both the rod and cap. Bruce uses Clevite 77 rod bearings with .003-inch clearanc. The side clearance should be adjusted to .022-inch.

The pistons are J.E. forgings with the pin hole relocated to compensate for the longer 240 rods used with the 300 crank. Only two ring grooves are used in teh pistons; the single compression ring is a .017-inch step Dykes with a .012-inch end gap; the three-piece oil ring is from either Perfect Circle or Sealed Power. The cylinder block's deck height is cut to place pistons .010-inch down in the bores. When used with a head gasket having a compressed thickness of .038-inch this gives compression ratio of approximately 12.0:1. The cylinders walls are honed to a 600 micro-inch finish with .007-inch piston-to-wall clearance.

The cylinder head is a 240 casting with porting work done by Crane. The combustion chambers are cleaned and the valves unshrouded, increasing the combustino chamber displacement from 67 to 70cc's. Cran experimented with a variety of port configurations, buth round and square (see photo), with the square ports proving to be surperior. in airflow testing, the Crane head has shown a 40% increase in flow over the stock 240 head. Surprisingly enough, this has been accomplished without a great change in the cross sectinoal area of the ports. Rather, the increase has been provided by the reshaping of the ports and runners.

The head is currently fitted with stock 327 Chevy intake and exhaust valves (1 15/16 and 1.600 inches, respectively), but later airflow tests have shown a slight improvement from the use of reworked 427 Ford valves. The valves are the lightweight hollow-stem versions and require that the stems be shortened and the head diameters be turned down to allow their use. New keeper grooves must also be cut in the stems. The advantage of the 427 Ford valves over the 327 Chevy valves at least from an airflow standpoint, lies in the contourof the underside of the valve head. The ford valve has a steep, smooth angle of approximately 23-degrees from the stem to the seat while Chevy valve has a more abrupt angle of apporoximately 10 degrees from the stem to the seat. Sizemore emphasizes, however, that the advantage has only been indicated in airflow testing, as they have not yet had a chance to actually try the Ford valves in the engine. The basic 427 Ford valves that are required for the modification are the 2.195-inch hollow-stem intakes (part number C5AZ-6505-N) and the sodium-filled 1.733-inch exhausts (part number C5AZ-6505-N). Be prepared for the much greater initial cost of the lightweight Ford valves as compared to the Chevy valves, not to mention the additional labor.

The valves are cut with 45-degree seats, while the heads get 44-degree seats for a 1-degree interference fit. The intake seats have a width of .040-inch; the exhausts have a width of .060-inch. "Preparation-H" uses General Kinetics valve springs with a seat pressure of 120 pounds, hard anodized aluminum retainers and Isky hardened keepers. Sizemore uses Sharp 1.6:1 needle-bearing, roller-tip aluminum rocker arms mounted on screw-in rocker studs from a high performance 289. Use the stock, silver-colored McCord matrix head gasket, part number C5AE-6015-B. The factory stocks two similar gaskets for these engines -- be sure you get the gasket marked with a small stamped-in "Mc" and not one with a stamped-in "V". Secure the cylinder head to the block using a hardened steel washer under the head of each bolt. Watch the length of the head bolts to avoid bottoming if you have milled either the block or the cylinder head surfaces. Torque the head bolts to 70lbs-ft, retorquing them after the engine reaches operating temperature.

The camshaft was purchased from General Kinetics and has 310 degrees of duration, a .372-inch lift at the cam (multiplied by the 1.6:1 ratio rocker arms, this gives a lift of almost .600-inch at the valve) and 90 degrees of overlap. Bruce isntalled the cam with split overlap which required the use of an offset 4-degree advance key supplied by Mr. Gasket. Stock 289 solid lifters are used with Smith Brothers' 3/8-inch O.D., heavywall, chrome-moly pushrods. The stock timing gear set should be discarded and replaced with a Cloyes gear set. The stock fiber cam gear has many small teeth that shear easily compared with the larger, much stonger teeth on Cloyes aluminum cam gear.

Bruce recommends two ways to go for ignition, either a Mallory Rev-Pol dual-point distributor or an Accel ball bearing dual point conversion kit for the stock 240-type distributor should be set to give 20 degrees of crankshaft advance (10 distributor degrees) at 3000 crankshaft rpm. Initial timing should be set at 18 degrees for a total of 38 degrees of advance. use Autolite BF-22 plugs gapped at .030-inch.

The exhaust was constructed from 1 3/4-inch O.D. tubing, with each pipe having a length of 34 inches from the flange to the beginning of the collectors. Cylinders, 1, 2, and 3 are grouped into one collector, whiel cylinders, 4, 5, and 6 are grouped into a second, separate collector. The collectors themselves have an inside diameter of 3 1/2-inches and an overall length of 9-inches. Sizemore again emphasies however that these particular headers are not a result of trial and error. They are the first onand only ones that have been tried on the car to date, and wil most likely be improved upon in the coming season.

The intake manifold, like the headers, was constructed of 1 3/4" tubing. The length of the tubing was cut accordingly to allow an overall length of 18 inches from top of the carburator horn to the intake valve seat. Using three 48mm, two-barrel Weber downdraft carbs, the tubing manifold was constructed to allow one carburator barrel to feed each of the six cylinders. No lenum chamber is used. The Webers are fitted with .170-inch main jets and .140-inch air correction jets.

The six lubricated by a stock oil pump that has had the pressure relief spring shimmed to provide 70 pounds of oil pressure. The oil pan sump was lowered to increase the capacity to nine quarts (less filter), and the oil pump pickup was lowered accordingly and positioned in the center of the sump. Valvoline 40-weight is used as lubricant.

The clutch and flywheel are all Schiefer units originally designed for 289-302-351 cubic inch V8's. The forged aluminum flywheel and 11-inch, 2800-pound forged aluminum pressure plate are both coated with a .010-inch sprayed steel surface for heat dissapation. The disc, part number 50-40128, is a special Shiefer item designed especially for Ford four-speed applications. Because of the six-cylinder's vibration, Bruce uses Locktite to secutre the 1/4x20x3/4-inch Schiefer bolts that hold the flywheel to the back of the crank. The entire clutch unit is housed inside a Lakewood 289 (6-bolt) scattershield.

The four-speed transmission is a small-input 2.32:1 low gear unit of the type used on 289's and low performance (Windsor) 302. If you're shopping around for a used trans, you should be aware that there is an almost identical four-speed that was used with the 390 engine. It has the small diameter input shaft and the same gear ratios, but the pilot on the main shaft is 5/8-inch shorter than the pilot used on the 289-302 transmissions. This difference will not allow the main shaft to seat properly in the rear of the crankshaft adn will ruin the clutch as well as the pilot bearing. Use the roller bearing developed for LeMans engines; either a Fafnir number 9103KDD or a New Departure number 773L03. The trans is equpped with a Hurst Competition-Plus shifter.

A shortened 428 Cobra Jet driveshaft connects the trans with a '69 Mustang rearend. The stock width rearend carries a 9-inch diameter ring gear in a 4.89:1 ratio, a Detroit Locker and stock 31-spline Mustang axles. The rear springs are stock six-clinder units used with adjustable Koni shcoks and 34-inch long tractino bars.

"Preparation-H" has shown that a six-cylinder engine can be built at at reasonable cost, developing enough power to move a 2800-pound Maverick well into the 11-second bracket. In its current form, the engine is putting out approximately 400 horsepower -- and more on the way.



As an example, the 295 hp net of the factory 302 hp gross rated Hemi 265 used 2.2 sq inches intake port area at gasket face per intake, 1.96" intake valves, 40 mm, 1.575" venturis
Cam duration lift figures...
306 to 312 Adv. Duration intake & exhaust
232 In 232 Ex .050" Duration
0.479" 0.479" gross lift at valve
110 LSA
HYD Lash Intake & Exhaust
Last edited by xctasy on Sat Sep 15, 2018 5:22 am, edited 1 time in total.
Image
XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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Re: Cam Selection for Weber DCOE carbs

Post #35 by THE FRENCHTOWN FLYER » Tue Aug 28, 2018 5:34 pm

My friend and 2-time IHRA Modified Eliminator world champ (wife Ann drove) used 48 mm Webers on his drag car, then switched to 58 mm, then to three Holleys on a common plenum. Then to a Chryseler hybrid sprint six engine (What a work of art!!!) with three split Dominators. Ran in the sevens.

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Missing you John. RIP

EDIT: Here are John and I and our wives after Ann won the Northern Nationals ca 1983. They were still running the Ford 300 and 58 mm Webers at that time.

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Re: Cam Selection for Weber DCOE carbs

Post #36 by xctasy » Sat Sep 01, 2018 7:08 am

I shake my head. Bless John P. He nailed it! TFTF has inadvertatly corroborated the evidence.


A cam and carb combintion that works is the Preperation H model, and it gets better idle with better acceleration.


Using 1.19 Holley 350 cfm carbs, or 1.38 Holley 500 cfm carbs in stock form is a waste of 60 foot acceleration and 1320 feet trap speed,

The problem John Peto found was the same as TFTF found in post #7 and #15, You guys had already split the atom....you just had to go over the facts again.

Smaller 1.1875" 30 mm venturis of the Triple 350 CFM 7448 Holley, loss of acceleration and speed everywhere. Upgrade of the too small 1.375" 35 mm venturi triple 500 cfm 4412 Holley's, more mph and acceleration.


The 2-bbl 650 ran 1.4375" venturis, getting better than 36.5 mm, but still way off the IR peaks for a 818 cc per cylinder engine. Ok for an I6 300 engine reving to 3600 rpm.

Former board useers panic said all this back in the late 00's, and no one listened to him then either.... :bang:

Mark P had the same issue when putting 6 carbs on his 6 cylinder Honda motorbike. He got the peak carb venturi sizes wrong, and he could never get it to perfortm right.


Triple carbs with 6V 30 mm and 35 mm are just too small for any I6 six above 250 cubes...way too small. You can rout out a 4412 to 39.6 mm by linsihing and epoxying up the open holes in the casting, or just get a set of Dominator Splits to go upwards of 43 mm or more.

Even they are too small for a 300 reving to 6500 rpm.

Guys, it wasn't CFM , it was ventrui size. CFM is a danged rotten way to measure the demands of a 6 bbl in line six. Air speeds are way down from the 265 to 289 feet per second of a normal 2-bbl or 4-bbl Holley on a 300 cubic inch engine. Adding two more cars, the air speed drops to allow pulse tunind, with zero duty time per jet. The 170 jets on the Preperation H with 42 mm venturis are like six 67 Holley jets.

cf.


Exhibit A, post #7
#7 by THE FRENCHTOWN FLYER » Tue Dec 12, 2017 wrote:
CNC-Dude wrote:One upgrade you can do is ditch the Webers and go to Holley's. We ruled H/MP for years with Webers and thought they were unbeatable until we swapped over to Holley's and gained close to 30 HP.


My old buddy, John Peto, two-time IHRA Modified Champion with his wife Ann driving (R.I.P. John), ran a series of six cylinder engines, first with 48 mm Webers, then 58mm Webers, then 500 Holleys, and finally split Dominators in an effort to get sufficient CFM to each cylinder. [Boy, his stuff was a work of art].
The Prep H manifold I acquired from Bruce also came with a common plenum with three Holley mountings. Care to comment about the differences you saw Bruce?
I know even my puny-by-comparison bracket engine needed more than three 500 cfm 2Vs. I fixed that.

For a street / strip engine three Weber style carbs will work OK.



cf.

Exhibit B, post #15
#15 by THE FRENCHTOWN FLYER » Sun Dec 17, 2017 wrote:I'll recount my experiences if you haven't heard this story before.
I decided to go the common-plenum-three-two route after switching to a 300 ci bracket combo from my 4V 243 ci D/ED combo.
I ran (3) 500s and it took more than a little time to get rid of the two main issues - too fat idle circuits and bog / stumble / flat spot off the line. Eventually I got it to work acceptably well. Then I switched to the crossflow head with a bigger runner intake and more flow.
At some point I thought three 500s might be too much.

[NOTE: A 500 CFM 2V flows the equivalent of 357 CFM 4V flow; a 350 CFM 2V flows the equivalent of 250 CFM.]

So I decided to build three tricked out 350 CFM carbs to see if it would pick up the car. I massaged them with 500 base plates with the main bodies taper bored to match up, down-leg boosters, internal mods, thinking three at the equivalent of 750 CFM 4V might better than the three 500s at the equivalent of 1070 CFM. To my surprise it was slower. Everywhere. 60 ft, 1/8 e.t., trap speed and e.t.
So I figured if smaller is worser bigger may be mo betta.
I modified the 500s to get an estimated 540 CFM. That has given me my best results. When you think about it that's about equivalent flow of a small Dominator, which seems about right for a 305 ci Comp motor.

The three 350s ended up on my vintage Logghe car to "slow it down" above 9.99.

And at some point I loaned Jerry Arnold three 650 annular discharge carbs to run on his Comp car. He did not like them much.

I guess I am saying on a U-flow head I would try three 500s to start out.



If your stuck, just grab three 4-bbl 650 Double Pumpers, or Holley 0-4224 4-bbl 660 cfm Center Quirters, and get the target area of over 45 mm venturis per cylinder by using two approximately 1.3125" venturis.

The old 1969 Z28 302 Camaro 4053 DZ Holley Carb Twin 4-bbl 650 carbs, matched to become three 650 4-BBLS.

The triple 4-bbls eclipse the triple 2-bbls 650 carbs for idealised Weber port area for a 819 cc per cylinder engine.


Used on the bored out 310 Chevy 292 engines CNC Dude pit crewed for, they made those combinations haul through the traps at 9000 rpm.

CNC Dude says triple 650 Holley 2-bbls, but I've seen three 4-bbl Z28 CrossRam carbs

viewtopic.php?f=2&t=77623&p=597769#p597769

CNC-Dude wrote:We used (3) 650 2bbl. Holley's. They are 2300 style carbs.


CNC-Dude wrote:Our 3x2 setup may have been overkill, but it was truly several steps above the performance the Weber's gave us, even though we were already running well into the 10's with them. We were running consistently in the lower mid-10's in H/MP with the Holley's before the class was ended by NHRA, with our best of 10.39@128 and some change in the Pocket Rocket Chevy II.
Last edited by xctasy on Sat Sep 15, 2018 5:19 am, edited 1 time in total.
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FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
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Re: Cam Selection for Weber DCOE carbs

Post #37 by Captainslow42 » Wed Sep 05, 2018 5:58 pm

Wow! Thankyou guys so much for all of this help, you've given me a LOT to think about. To be honest, I've actually been a bit unsure about using the side drafts these last few months (although I've been looking for good reasons to use 'em). Aside from trying to manufacture my own intake, where can I get one apart from Clifford? When I talked to Larry, he was uncertain about casting new ones, and couldn't give me either a price or a projected delivery time even if he were to go ahead. I guess price would be dependent on the demand for new castings? I'm not sure how I feel about running a setup without a provision for vacuum advance or carb heat in my street machine. And correct me if I'm wrong, but aren't they fairly sensitve to changes in temperature/ atmospheric pressure? Part of me really wants the challenge of tuning those webers up perfectly, but I also don't want a car that wont run right when the weather gets cold, or hot, or a bit damp. I still really like the IDEA of a row of DCOEs on the side of my 300, but I'm worried I would be dissapointed with day to day driveability. I still have the carbs sitting on my shelf though...

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I also currently have an Edelbrock 1405 4 barrel (a gift from my father who had one) which I have cleaned up and installed a rebuild kit in. I am considering picking up an Offy "C" manifold and bolting them together. Do you think this carb and manifold would suit my build or in your opinion should I persevere with the triple weber setup? I'd like to use them but I'm not sure if I'm prepared to extensively modify them for my first ever build.

Thanks again for the huge amount of information being shared on this forum, it's great to be a part of a community where experienced builders and racers can share so much with the rest of us! :beer:

Jesse

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Re: Cam Selection for Weber DCOE carbs

Post #38 by Captainslow42 » Wed Sep 05, 2018 6:33 pm

Also, just for information sake, I'll post a few more details about my plan for the rest of the build. I plan on running a Mustang T-5 trans (relatively cheap for what it is, and it'll bolt right up to my bellhousing) with an S-10 tailshaft conversion to move the shifter out from under my bench seat. This will be connected to a shortened 8.8 rear with 3.73 gears. I'm hoping to have the whole thing sitting on 15 inch steel rims.I assumed 24 inches overall tire diameter when I plugged these numbers into a couple of drivetrain calculators, but I havent gotten as far as actually choosing specific tires.

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Does this all make sense or am I just going in the wrong direction entirely? I feel like these ratios make sense for how I want to use the car.

Jesse

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Re: Cam Selection for Weber DCOE carbs

Post #39 by pmuller9 » Wed Sep 05, 2018 6:54 pm

Stay with the Weber DCOE plan.
I agree that they are small for a 300 six if each barrel feeds a single cylinder.
However you can cheat by having each weber mounted to an individual plenum that has two runners, each runner connected to one of two cylinders.
This way each cylinder is being serviced by both barrels of the Weber.

I hope I made that clear enough?

Have you started on the engine build yet?

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Re: Cam Selection for Weber DCOE carbs

Post #40 by Captainslow42 » Wed Sep 05, 2018 7:29 pm

Very clear :)

would I be able to cut a 2 runner section from a stock log manifold, weld up the ends, and mill down the side of the plenum to afix a flange for the carb? or would I be better off starting from scratch with flanges for the head and for the carb?

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Uh, unfortunately not yet, I've been disassembling and cleaning up what I can. But for most of the work, I'd like to have the engine on a stand in a controlled environment and the space I was offered to work in is still being a built. I am currently apprenticing as a heavy diesel tech, so anything I can wheel into the shop I can work on during the day, I just cant leave it there when I go and I don't want to constantly move eveything around :p I know I'm probably getting ahead of myself with all of these questions, but I just like to plan ahead as much as I can.

Any thoughts on Manifold vacuum? If I run vacuum lines from each of the three plenums into a small canister or chamber to smooth out pulses in the vacuum signal, should it be strong and consistent enough to use the vacuum advance on my dizzy?

Thanks

Jesse

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Re: Cam Selection for Weber DCOE carbs

Post #41 by pmuller9 » Wed Sep 05, 2018 10:08 pm

I was thinking about cutting the lower half of the EFI intake manifold short just before the bend and welding the 3 plenums to it.

I vacuum canister might work if it had a small volume. A large volume would create a delay in response for the vacuum advance.
It would be best if the 3 lines just went to a 3 to 1 connection and used the volume in the vacuum advance canister.

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Re: Cam Selection for Weber DCOE carbs

Post #42 by xctasy » Sat Sep 08, 2018 10:55 pm

Triple Webers are probably the best package to go with because they lend themselves to 'pulse - tuning' (Timing the pulse to coincide with the next intake filling charge). That complements the fat torque curve situation.


But if your gonna restrict it and ignore all the Aero engine development work done between World War I and II by Weber, and all the work done by everyone else the world over, go for it.

Be prepared to be very disappointed.

Plenty of promising development has been done on single four barrel Holleys by altering the tune length of the intake runners, but it awlays comes out under the best 6bbl Webers with a few exceptions being the TR6, GT6, and Datsun 240/260/280Z engines....aftermarket 4-bbls in some cases go better, but thats a DCOE Weber issue in the 32 to 35 mm venturi area, where a 40, 42 Oor 45 DCOE can vary as to its ideal best flow for a 32 to 35 mm venturi.


With the double pumper or mec sec 390 or 465 on the little Datsuns, its a 4-bbl venturi to throttle size issue, and its well documented that a good US intake can be better than any 6V system.

In this instance, no way will combining runners with more volume help deliver fuel to the combustion chamber if the gross venturi area is less than the Weber graph for the rev range. Period. Its not a NASCAR engine, so you cannnot get the cam to increase the vaccum to improve fuel delivery.

IMHO, 36's won't work, because pulse tunning cannot occur at the velocity and the pulse frequency required. Its out of range, and adding volume won't help deliver fuel to neady cylinders. Reducing air speed and reducing duty time results in more air fuel to the engine. Weber DCOE's really do stall the air speed to less than 17 feet per second, and when it goes up, massive dollops of horsepower are spirited away by increased bounadry layer action.


Flow is number of flow pats, under number of flow drops, and reducing the venturi diameter is like shoving sandbags at a water wheel running a saw mill. It impeds flow. Another boundary is added to something that normally works 100% if you follow the rules.

I've plotted every in line six with six barrel Weber IDA, IDF, IDF3C and DCOE/DCO/ Dellorto DHLA carbuation. None of it is like a 340 or 440 Six pack, where you just add volume, and sync up the carbs,....you just cannot create adequate cylinder filling when the volume is siamesed to create a more favorable bathtub of fuel standoff. Carburation like, say, a Six barrel system doesn't work when the venturi sizes are sub optimal. Adding duty time to each venturi from another cylinder sounds fine in theory, but its unable to add the fuel supply that is taken away. Jet sizes are always 1/16 to 1/25th of the venturi size as well. Dunno how you can deal with reducing the ideal venturi sizes, and then find a way to increase jet size.


All the Holden guys would have had to have done in 1973 was keep the log intake, and down grade to smaller venturis. All the Chrylser Hemi 265 6 pack guys would have done was the same from 1971 to 1973. THE Mini Cooper S 1275'S for the Monte Carlo Rallye Would have done the same. They didn't, because no one kind of sub joined port on port system ever showed an increase of power or torque at any range. If it was that easy, it would have shown up in dyno tests.


Vizard did a combined log intake system for twin carbs or split Webers, and he did find gains through the process of making flow dams, but it was not an IR port on port engine.

Enjoy making your own decsions, and good luck with the project guys.
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Re: Cam Selection for Weber DCOE carbs

Post #43 by pmuller9 » Sun Sep 09, 2018 12:35 am

I understand that disrupting a single tuned pathway between the venturi and intake port with a plenum is in conflict with the Weber design and not ideal.
So let's revisit a no plenum, IR approach and please keep it specific to this engine build.
Please keep in mind that the OP stated that the interest is in moderate street performance.

If this 300 six makes peak power (maybe 250 hp) at 4500 rpm and will rev limit to 5000 rpm, what would the ideal venturi size be?

If the present Weber 45 DCOE with 36mm venturi are used at what point would you expect power to be sacrificed?

Thanks for your input.

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Re: Cam Selection for Weber DCOE carbs

Post #44 by xctasy » Sun Sep 09, 2018 5:53 am

Live forever, PM.

pmuller9 wrote:....

If this 300 six makes peak power (maybe 250 hp) at 4500 rpm and will rev limit to 5000 rpm, what would the ideal venturi size be?

If the present Weber 45 DCOE with 36mm venturi are used at what point would you expect power to be sacrificed?

Thanks for your input.



I get 40 mm for power at 4550 rpm, Thats about the biggest you can get in a DCOE45.


The calculation variable for 819 cc per cylinder is Critical Flow condition. An Air restrictor would be Venturi meter with Cd about 0.85

http://www.performanceoriented.com/throttle-body-and-main-venturi-sizing/ wrote:The following main venturi selection chart was generated using classical venturi sizing formulas and is based on a sizing coefficient of .80 for the venturi diameters. Additional tailoring of the formulas was performed to help fit the data to agree with actual OEM production and race engine configurations.


I took a risk and used PMO's copywrited material.

Image


"Weber_pmo_derived" is the extrapolated result.


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I get 43 mm at 5500 rpm, and the black line is about 3600 rpm. Way too low for a 300 cubic inch six with 819 cc per cylinder.


I get 3600 rpm with the 36 mm venturi a huge restriction to the elastic rev range required to run an IR system, and conventional US multiple carb logic doesn't work unless the air speeds are dropped.

CFM is a truley bad way of rating a multiple carb installation on a 300 cube six.

Although the flow losses of the 45 DCOE will flat line well below 36 mm, the losses between 38 to 40 mm are huge on a DCOE 45

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Last edited by xctasy on Sun Sep 09, 2018 10:15 am, edited 2 times in total.
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FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
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Re: Cam Selection for Weber DCOE carbs

Post #45 by pmuller9 » Sun Sep 09, 2018 10:13 am

The Weber 45 DCOE 36mm choke would be a good fit for a bone stock 300 where the peak power is close to 3500 rpm.

xctasy wrote:I get 40 mm for power at 4550 rpm, Thats about the biggest you can get in a DCOE45.
Last edited by pmuller9 on Sun Sep 09, 2018 10:22 am, edited 3 times in total.

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Re: Cam Selection for Weber DCOE carbs

Post #46 by xctasy » Sun Sep 09, 2018 10:16 am

Talk with World ChampGramp and pmuller regards this. The head work should follow the latest developments with the 300.


That big old six will hit the 320 flywheel or 270 rwhp if its got a manual gearbox.

The cam it would like would be 580 lift, 264 at 50 thou, and try a greater than 110 lobe center.


Go to 40 mm's as a compromise with all the 45 DCOE parts you have, and set it up as per an E49 Mopar 265 above .


Follow pmullers advice, use the EFi lower half, and mount the Webers the way Paul Knott did on his 1961 Ford Falcon.


Used the Mercury 390 vacuum canister for vac takeoff to the brake booster, like Paul has done.


He used the same base with three DCOE 45 Webers. Got 280 hp at the flywheel at 6500 rpm from 170 cubic inches

Image
Image

ImageImage


Good fortune with the build.
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FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
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Re: Cam Selection for Weber DCOE carbs

Post #47 by THE FRENCHTOWN FLYER » Sun Sep 09, 2018 11:28 am

That's a pretty engine. Impressive numbers too.
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Re: Cam Selection for Weber DCOE carbs

Post #48 by Lunatic Fringe » Sun Sep 09, 2018 1:46 pm

Image[/URL]
Sorry for the poor quality, it's a screenshot of a VHS video shot in 1985. 3 Webers hiding behind an air filter on a 300. Very strong runner, the engine originally was in a Modified Production 60's Mustang.

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Re: Cam Selection for Weber DCOE carbs

Post #49 by xctasy » Sat Sep 15, 2018 6:33 am

Even below 500 hp, Cotton Perry and the late Jim Hedrick found out that IDA 48 Weber 2-bbls had restrictions in terms of total venturi area.

After 1978, In terms of net venturi area to support an independent runner intake, they found it was its pretty hard to beat this for a 292-300-310 cubic inch in line six


Image


Above you are three 780 or 800 cfm carbs. (Not installed from the factory, but available as an "over the counter" service item only, the 1968 -1969 Holley 4bbl Camaro 302 Dual Quads List #'Numbers replacement #4210 or new ex dealer # 4053 or #4295)


For the Chevy II with its 292, they were used to get the rev range into the usefull 7000 to sometimes 10000 rpm bracket. Three Holley 4-bbl 4150 PN 3923289 DZ Holley # 4053 PN 3957859 Holley # 4295 carbs were based on the old 396 350-375 or 427-430 hp and similar to the later 290 hp Boss 302/390 FE pr GTHO 351 Phase III carbs.Those all have a ventrui area of about 3.108 sq in per two barrels. That's the same as One 2" venturi, and supports about 650 hp at 8400 rpm for approximately 820 cc per cylinder on a 300 cube six.



See https://www.12bolt.com/cotton-perry.html



On barrel of a ID 48 has a nominal venturi of about 42-44 mm, so a 43 mm venturi is 2.25 sq inches. A 600 4-bbl Holley, or a 660 center squirter 4-bbl has 2.58 sq inches per 2-bbl, or 5.16 sq inches total from Table J, total Venturi area.


That's about right for a 300 six reving to 5500 rpm.


The idealised Weber IR curves are still the optimum,, but as stated before, you can grab three 4-bbl carbs, and phase each 2-bbl to equal the total venturi area of a bigger Weber DCO or IDA/IDF carb without the expense.

Best bet are 1:1 linkages for secondary operation, and conversion to Four coner idle, but 4-bbls pulse tune just like a Weber if the net venturi area is matched to the peak power rpm level.


"Pulse tuning" for carbs only happens at about 11 to 18 feet per second of air flow, so you have to go big. Forget all that CFM flow rate hocus pocus. Only focus on the ventrui area required to match the peak power rpm. Then engine will rev above the peak power rpm. 5500 rpm is a good figure to punt for.


Your limit is the space under the hood, and the proximity to the spring tower braces or spring towers if its an XK 200 based X shell Ford your slapiing the 300 into.

See http://fordsix.com/forum/viewtopic.php?f=5&t=8106


The 44 carby Chronicals covers the comon 1, 2 and 4-bbl Holley carbs


Its in imperial, not metric.


See line 11, 12, 14, 18 and 19


13, the 4360 series 540 cfm 4-bbl, is not a good option, the are a small Quadrajet, Thermoquad and 4350 Auotlite replacment which had its uses, and there are ones around, and if its cheap, why not. Don't expect it to work well, its not easily adjustable.

I'd eliminate it as an option because its old and not the best quality, it does suit small V8's and V6's. I'd personally not use any 4010, or 4011 series 4-bbl, but its around, and has been put into production again after being withdrawn by Holley in the learly 90's. In the past, it was poor quality.

The fields are:
A. |No| is the line number of the chart,
B. |number|, the series model, not the part number.
C. |CFM| the cubic feet per minute quoted at whaever flow drop
D. |Pri B"| is the Primary throttle bore diameter in inches
E. |Pri V"| is the Primary venturi bore diameter in inches
F. |VentASQ| is the square inches of primary venturi area
G. |Signal|, the amount of intrusion of the venturi relative to the throttle diameter. Higher the %, higher the signal.
H. |Sec B"| is the secondary throttle bore diameter in inches
I. |Sec V"| is the secondary venturi bore diameter in inches
J. |Total V AREA| is the all up venturi area in the carb, primary plus secondary.
K. |Air SPD| is the actual flow speed at the cfm supplied. Maximum power happens at 200 to 300 ft/sec, so if someone has a flow rate of 488 ft/sec, then its not going to produce easy power there, and the cfm is likely to be optimistic
L. |PriBHP| is the maximum net power at 1.5"Hg for the primary ciruit
M.|Total BHP| is the maximum net power at 1.5"Hg



01|#2110-|200-|2-bbl|1.4375-|1.3125|1.353---|09.5-----|----------|---------|1.353-------|355FT/sec|102bhp|102bhp|
02|#5200-|230-|2-bbl|1.2800-|1.0400|0.849---|23.1-----|1.4375-|1.0625----|1.736|318FT/sec|043bhp|102bhp|
03|#5210-|255-|2-bbl|1.2500-|1.0300|0.833---|21.4-----|1.6875-|1.2800----|2.120-----|289FT/sec|050bhp|113bhp|
04|#5200-|280-|2-bbl|1.2800-|1.0400|0.849---|23.1-----|1.4375-|1.0625----|1.736-----|387FT/sec|061bhp|124bhp|
05|#6520-|280-|2-bbl|1.2800-|1.0400|0.849---|23.1-----|1.4375-|1.0625----|1.736------|387FT/sec|061bhp|124bhp|
06|#2110-|300-|2-bbl|1.4375-|1.3125|1.353"---|09.5-----|---------|------------|1.353------|532FT/sec|153bhp|153bhp|
07|#4150-|340-|2-bbl|1.4375-|1.0625--|1.7730-|35.3-|1.4375-|1.0625-|3.547--|~230ft/sec|106|213|
08|#2305-|350|2-bbl-|1.5000--|1.1875--|1.1075-|26.3-|1.500--|1.1875-|2.205--|~379ft/sec|84--|168|
09|#2300-|355|2-bbl-|1.5000--|1.1875--|2.2150-|26.3-|---------|---------|2.215--|~385ft/sec|-----|170|
10|#4150-|370|4-bbl-|1.43750-|1.0625--|1.7730-|35.3-|1.4375|1.06250-|3.547-|~250ft/sec|116|231|
11|#4150/60|390|4-bbl-|1.4375-|1.0625-|1.7730-|43.7-|1.4375|1.06250-|3.547-|~264ft/sec|122|244|
12|#4160-|450|4-bbl-|1.5000--|1.0938--|1.8979-|37.1-|1.5000|1.0938--|3.5310| ~306ft/sec|141|281|
13|#4360-|450|4-bbl-|1.3750--|1.0625--|1.7730-|29.4-|1.4375|1.1875--|3.988--|~270ft/sec|133|281|
14|#4160-|465|4-bbl-|1.5000--|1.0938--|1.8790-|37.1-|1.500-|1.0938--|3.759-|~297ft/sec|146|291|
15|#2300-|500|2-bbl-|1.6875--|1.3750--|2.9700-|22.7-|--------|----------|2.9700-|~404ft/sec|----|221|
16|#2305-|500|2-bbl-|1.6875--|1.3750--|1.4850-|22.7-|1.6875|1.3750-|1.4850-|~404ft/sec|111|221|
17*|2300-|500|2-bbl-|1.750--|1.3750--|2.9700-|27.3-|--------|----------|2.9700-|~404ft/sec|----|221|
18|#4160-|550|4-bbl-|1.5000--|1.1875--|2.2150|26.5-|1.5000-|1.2500-|4.6690-|~283ft/sec|168|344|
19|#4150/60|600|4-bbl-|1.5625--|1.25000--|2.4540|25.0-|1.5625-|1.3125-|5.1600-|~279ft/sec|183|375|
20|#4180-|600|4-bbl-|1.5625--|1.2500--|2.4540|25.0-|1.5625-|1.3125-|5.1600-|~279ft/sec|183|375|
21|#4010-|600|4-bbl-|1.5625--|1.2500--|2.4540|25.0-|1.5625-|1.3125-|5.1600-|~279ft/sec|183|375|
22|#2300-|650|2-bbl-|1.7500--|1.4375--|3.2460|21.7-|---------|---------|3.2460-|~481ft/sec|-----|288|
23|#4011-|650|4-bbl-|1.3750--|1.1560--|2.0990|18.9-|2.000--|1.3750-|5.069--|~308ft/sec|185|406|
24|#4165-|650|4-bbl-|1.3750--|1.1560--|2.0990|18.9-|2.000--|1.3750-|5.069--|~308ft/sec|185|406|
25|#4160-|660|4-bbl-|1.6875-|1.2500--|2.4540|35.0-|1.6875-|1.2500-|5.160---|~307ft/sec|-----|413|
26*|4160-|700|4-bbl-|1.6875-|1.5625--|3.8350|08.0-|1.6875-|1.5625-|7.670---|~219ft/sec|219|438|
27|#4150-|700|4-bbl-|1.6875-|1.3125--|2.7060|28.6-|1.6875-|1.3750-|5.676---|~296ft/sec|214|438|
28|#4150-|725|4-bbl-|1.6875-|1.3125--|2.7060|28.6-|1.6875-|1.3750-|5.676---|~307ft/sec|221|453|
29|#4150-|750|4-bbl-|1.6875-|1.3750--|2.9700|22.7-|1.6875-|1.3750-|6.216---|~290ft/sec|229|469|
30|#4010-|750|4-bbl-|1.6875-|1.3750--|2.9700|22.7-|1.6875-|1.3750-|6.216---|~290ft/sec|229|469|
31|#4150-|780|4-bbl-|1.6875-|1.3750--|2.9700|22.7-|1.6875-|1.3750-|6.216--|~301ft/sec|238|488|
32|#4011-|800|4-bbl-|1.3750-|1.1560--|2.0990|21.7-|2.000--|1.71875|6.739--|~285ft/sec|201|500||
33|#4150-|830|4-bbl-|1.6875-|1.5625--|3.8350|08.0-|1.6875-|1.5625--|7.670--|~260ft/sec|260|519|
34|#4150-|850|4-bbl-|1.7500-|1.5625--|3.8350|12.0-|1.750--|1.5625--|7.670--|~266ft/sec|265|531|
35|#4150-|855|4-bbl-|1.7500-|1.5625--|3.8350|12.0-|1.750--|1.5625--|7.670--|~268ft/sec|267|534|
36|#3160-|950|3-bbl-|1.7500-|1.5625--|3.8350|12.0-|1.75 x 3.625|1.5625 x 3.4375|8.682|263ft/sec|297|594|
37|#4150-|950|4-bbl-|1.7500-|1.5625--|3.8350|12.0-|1.750--|1.5625--|7.670--|~297ft/sec|297|594|
38|#4500-|1050|4-bbl-|2.000-|1.6875--|4.4731|18.5-|2.000--|1.6875--|8.946--|~282ft/sec|328|656|
39|#4500-|1150|4-bbl-|2.000-|1.8125--|5.1603|10.3-|2.000--|1.8125--|10.3206|~267ft/sec|360|719|
40|#4500-|1150|4-bbl-|2.080-|1.8125--|5.1603|14.8-|2.080--|1.8125--|10.3206|~267ft/sec|360|719|
41|#4500-|1150|4-bbl-|2.100-|1.8125--|5.1603|15.9-|2.100--|1.8125--|10.3206|~267ft/sec|360|719|
42|#4500-|1150|4-bbl-|2.130-|1.8125--|5.1603|17.5-|2.130--|1.8125--|10.3206|~267ft/sec|360|719|
43|#4500-|1150|4-bbl-|2.160-|1.8125--|5.1603|19.2-|2.160--|1.8125--|10.3206|~267ft/sec|360|719|
44|#4500-|1150|4-bbl-|2.190-|1.8125--|5.1603|20.8-|2.190--|1.8125--|10.3206|~267ft/sec|360|719|



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XEC Ltd ICBE's Inter Continental Ballistic Engines-
FAZER 6Bi (M112 & EEC5) or FAZER 6Ti (GT3582 & EEC5) 425 HP 4.1L/250 I-6
FAZER 6V0 3x2-BBL Holley 188 HP 3.3L/200 I-6 or 235 HP 4.1L/250 I-6
X-Flow Engine Components Ltd http://www.xecltd.info/?rd=10

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