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Whats Next

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TeamNeptune
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Whats Next

Post #1 by TeamNeptune » Sun Oct 21, 2018 10:50 am

This is what I have done so far. What if anything is not correct for my usage. What should be considered for improvements in performance.
I have a 1978 ford Ranger 4x4 with 35" tires. T18 trannie. I primarily use it to pull my boat. It has a reconditioned block that is stock as far as I know.
Here is the list of modifications I have done.
Edelbrock 500 carb. mechanical sec. re-jetted secondary's to match the primaries.
Clifford 4bbl. intake
Comp. cam 268
early 60's 240 head tapped for 7/16 rocker studs with stock rockers, (intake 1.875) (exhaust 1.60) performance valves. No porting.
efi exhaust manifolds.
I am currently installing 4.11 differential gears to offset the over sized tires. It will take a while for me to recover from this expense.
Tires I know are costing me but I just like the way they look and it will se some 4 wheeling during hunting season.
Cam ??.. Larry says it is all wrong and should replace with his. With the 4.11's I will be hauling on the highway at around 2700 rpm and I wanted the engine to have a slight lope . I like the sound.
The only problem that I was having and keep in mind this was before the gear swap is staying up to speed on the highway.
long hills would cause my speed to drop off from 70mph to 55mph frequently.
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Fordman75
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Re: Whats Next

Post #2 by Fordman75 » Sun Oct 21, 2018 3:23 pm

The gears are the right step. If you current combo is tuned right you will have no issues running at highway speeds.

And Larry is the last person I would take build advice from.
Ted

54 Ford F100/F150 4x4
300, NP435 4spd, NP205 transfercase

pmuller9
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Re: Whats Next

Post #3 by pmuller9 » Sun Oct 21, 2018 4:25 pm

Your combination is good. The Comp 268 cam should make plenty of torque from 2000 rpm and up.
Was the cam installed as recommended with the intake lobe center near 106 degrees ATDC?

What is the ignition timing at idle and full mechanical advance at 3000 rpm with the vacuum advance disconnected?

TeamNeptune
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Re: Whats Next

Post #4 by TeamNeptune » Sun Oct 21, 2018 6:41 pm

I installed the camshaft as per directions. Seems like I remember it only being marked to go one way. As far as timing I would have to recheck it to be sure. I should probably check it at 3000. The timing at Idle was close to 10 deg. advanced with the vacuum unplugged. I advanced it some from there until I was hearing some valve rattle then backed it off just a touch. Last time I hauled the boat out it was with the 3.50 gearing I was at WOT at least 1/3 of the time and got just over 11mpg.
I will check the total advance at 3000. The vacuum seems to work best off of manifold.
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jason832
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Re: Whats Next

Post #5 by jason832 » Sun Oct 21, 2018 9:08 pm

I have a similar setup as you. 4barrel street demon, Clifford intake, headers, 268 cam, no head work, 4 inch lift, 3.55 gears, np435, 35inch bfg km2s. I have my timing tuned quite well and a wideband AFR meter. I have the street demon tuned very crisp. I rarely count milage but on a long haul if I hold 60mph I can nearly crack 20mpg not towing. I did one trip with a tandem axle car hauler and burned around 14mpg at 60mph. I cruise just touching the gas at less than 5% on level ground...

How heavy is that boat? Looks like a pile of weight and air drag. 11mpg prob isn't that bad....

The vacuum advance should be on ported vacuum. There's a spot somewhere on the carb for it. Check the vacuum advance arm moves a tad when you blip the throttle. Once timing is right start thinking wideband AFR meter if you want to push milage. The 3.55 gears will do fine unless you tow regularly. The cam should also be good, not perfect for towing but great for an empty truck.

TeamNeptune
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Re: Whats Next

Post #6 by TeamNeptune » Mon Oct 22, 2018 5:12 am

Jason how about a picture.
I think my boat is right around 2000lbs. I don't know where you live but out on the highway here between Charlottesville and Va Beach everybody and there grandmother will be flying by you if your doing 60mph. I can see 65mph while pulling the boat but empty, at least on the interstate I would be at 75mph. I live 30 miles east of the Blueridge mountains and its not exactly flat ground. When the truck is not pulling and empty and on flat ground yes I don't need to be into the throttle much either. They sent me the wrong dif.carrier for my dana 44 or the gears would have been done this weekend. I expect to be cruising the backroads here in the 1700-1800 rpm range at 45- 50mph with the new gears.
What type of AFR gauge do you have ? I am thinking that is a good idea.
After reading post for about 2hrs. last night I am a little concerned my Edelbrock 500 may be lean in the secondary. Plugs have been looking right, with just a small amount of tan but I would like to be able to see whats going on with the fuel mixture. Like I was saying I have the Eddy 500 jetted the same on both sides.
Thanks for your help, JD

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Re: Whats Next

Post #7 by Daubee 1978 » Mon Oct 22, 2018 7:53 am

I'm thinking your boat and trailer a considerably heavier than 2000.

jason832
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Re: Whats Next

Post #8 by jason832 » Mon Oct 22, 2018 8:12 am

I don't think the weight is too much of an issue until he hits a good hill, which he can downshift to 3rd if he needs to, that cam will pull well at 4000rpm. Pulling that truck and boat on level ground at highway speed is like 2 parachutes.... I've pulled a lot more than 2000 without much problems.

My AFR ratio gauge is the popular aem one. It works very well, you can see the change one jet size has easily.
https://www.summitracing.com/parts/avm-30-4110

If the truck doesn't spend much time on the highway empty, I would support 4.10s. But on the other side of the argument, how much gas could you have bought with that money.... Even going down to 33s on your next tire set would make a difference.

TeamNeptune
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Re: Whats Next

Post #9 by TeamNeptune » Mon Oct 22, 2018 2:03 pm

Jason at the miles I drive it will be 5 years before needing new tires.
It looks like your carb is facing north to south. I am thinking about going 1 step up on my secondary jets and just keep my foot out of it until the rpm’s are up. I don’t think dropping to 3rd is a good option. JD

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THE FRENCHTOWN FLYER
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Re: Whats Next

Post #10 by THE FRENCHTOWN FLYER » Mon Oct 22, 2018 5:04 pm

TeamNeptune wrote:...After reading post for about 2hrs. last night I am a little concerned my Edelbrock 500 may be lean in the secondary. Plugs have been looking right, with just a small amount of tan but I would like to be able to see whats going on with the fuel mixture. Like I was saying I have the Eddy 500 jetted the same on both sides.
Thanks for your help, JD


While I do not have a lot of experience with Edelbrock carbs specifically I can tell you that many four barrel carburetors are jetted on the lean side on the primaries. Carb makers want you to get as much fuel economy as possible. To compensate for the overly lean primaries the secondaries are often calibrated to be rich-of-optimum, so that the overall mixture going into the engine at WOT is near correct.

Soooo, if you leaned the secondaries to match the primaries you now have an overall too-lean mixture when pulling heavy loads, as you suspected.
FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

TeamNeptune
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Re: Whats Next

Post #11 by TeamNeptune » Mon Oct 22, 2018 5:29 pm

THE FRENCHTOWN FLYER wrote:
TeamNeptune wrote:...After reading post for about 2hrs. last night I am a little concerned my Edelbrock 500 may be lean in the secondary. Plugs have been looking right, with just a small amount of tan but I would like to be able to see whats going on with the fuel mixture. Like I was saying I have the Eddy 500 jetted the same on both sides.
Thanks for your help, JD


While I do not have a lot of experience with Edelbrock carbs specifically I can tell you that many four barrel carburetors are jetted on the lean side on the primaries. Carb makers want you to get as much fuel economy as possible. To compensate for the overly lean primaries the secondaries are often calibrated to be rich-of-optimum, so that the overall mixture going into the engine at WOT is near correct.

Soooo, if you leaned the secondaries to match the primaries you now have an overall too-lean mixture when pulling heavy loads, as you suspected.

Yes that would seem to be the case. I hope nothing has been hurt in the engine.

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Re: Whats Next

Post #12 by THE FRENCHTOWN FLYER » Mon Oct 22, 2018 5:51 pm

I doubt that any damage occurred. It might take sustained running with an overly lean condition to do permanent damage as the carb is probably not calibrated that far from optimum.

When I worked on the Mustang 5.0 GT program we had some secondary metering plates made up that corrected the fat secondaries and when installed in conjunction with a jet change to the primaries it perked up that ol' girl a bit more. Not available to the motoring public of course.
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TeamNeptune
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Re: Whats Next

Post #13 by TeamNeptune » Mon Oct 22, 2018 6:03 pm

I am still searching but last I read was with the 240 head and large cam you should be running at least 89 octane ?? I have the COMP cam 268 would this be true in my case.
JD

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Re: Whats Next

Post #14 by pmuller9 » Mon Oct 22, 2018 7:01 pm

TeamNeptune wrote:I am still searching but last I read was with the 240 head and large cam you should be running at least 89 octane ?? I have the COMP cam 268 would this be true in my case.
JD

The Comp 268 cam has the same advertised duration as the stock cam so if you use the 240 head and raise the compression to 8.8 or more you cannot install the 268 to the cam card spec which is intake lobe center at 106 degrees ATDC without detonation.
The stock cams intake lobe center sits at 114 degrees which gives you a much lower Dynamic compression ratio that the Comp 268.

If you use one of the other brand cams like Crower or Schneider, they have advertised durations of 280 to 284 for near the same Comps .050" duration of 218 degrees.
Then you can use any grade pump gas you want with a 9:1 compression ratio.

TeamNeptune
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Re: Whats Next

Post #15 by TeamNeptune » Tue Oct 23, 2018 4:38 am

pmuller9 wrote:
TeamNeptune wrote:I am still searching but last I read was with the 240 head and large cam you should be running at least 89 octane ?? I have the COMP cam 268 would this be true in my case.
JD

The Comp 268 cam has the same advertised duration as the stock cam so if you use the 240 head and raise the compression to 8.8 or more you cannot install the 268 to the cam card spec which is intake lobe center at 106 degrees ATDC without detonation.
The stock cams intake lobe center sits at 114 degrees which gives you a much lower Dynamic compression ratio that the Comp 268.

If you use one of the other brand cams like Crower or Schneider, they have advertised durations of 280 to 284 for near the same Comps .050" duration of 218 degrees.
Then you can use any grade pump gas you want with a 9:1 compression ratio.

Ok I read that quote last night from a previous post. I installed the 268 @ 4* advance which was recommended by comp cams.
So you are saying I will have detonation with any grade of gas or I should go up to 89 octane ?

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Re: Whats Next

Post #16 by TeamNeptune » Tue Oct 23, 2018 5:00 am

Right now my truck has the front wheels axles and gears out waiting on the carrier to come in. I don't really want to start it and rev it up to 3000 to check where the timing is with it being on jack stands. This weekend weather permitting I will have it back together.
I will check and see where it is at 3000 rpm and also 2700 rpm which is where it will likely be seeing most of its WOT.
Where should the mechanical advance from the distributer be at 2700 rpm ?
I would say 34 btdc

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Re: Whats Next

Post #17 by pmuller9 » Tue Oct 23, 2018 11:18 am

34 to 36 degrees total advance is a good place to be for ignition timing.
You said that you moved the timing till there was detonation and then backed off a little.
If you find that you are at 34 degrees at 2700 to 3000 rpm then all is good.
if the timing is less then you can go to 89 octane to see if you can advance the timing closer to 34.

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Re: Whats Next

Post #18 by Lazy JW » Tue Oct 23, 2018 12:22 pm

TeamNeptune wrote:... out on the highway here between Charlottesville and Va Beach everybody and there grandmother will be flying by you if your doing 60mph. I can see 65mph while pulling the boat but empty, at least on the interstate I would be at 75mph...


Whee! :D

I don't remember ever having my ol' White Ox going THAT fast! :mrgreen: :shock: :lol:
"The White OX" 1974 F-350 300-6, Stock single exhaust, Carter YF, T-18A, Dana70 w/4.11, Flatbed dually w/dump bed. "Where no oxen are, the crib is clean, but much increase is by the strength of the ox" (Proverbs 14:4)
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Re: Whats Next

Post #19 by Fordman75 » Tue Oct 23, 2018 4:25 pm

Lazy JW wrote:
TeamNeptune wrote:... out on the highway here between Charlottesville and Va Beach everybody and there grandmother will be flying by you if your doing 60mph. I can see 65mph while pulling the boat but empty, at least on the interstate I would be at 75mph...


Whee! :D

I don't remember ever having my ol' White Ox going THAT fast! :mrgreen: :shock: :lol:


I use to run faster then that with my old 86 F150 stock 300/4spd 2wd 3.08 gears, 31" rear tires pulling a loaded 20 foot car trailer.
Ted

54 Ford F100/F150 4x4
300, NP435 4spd, NP205 transfercase

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Re: Whats Next

Post #20 by bubba22349 » Tue Oct 23, 2018 5:08 pm

TeamNeptune wrote:Right now my truck has the front wheels axles and gears out waiting on the carrier to come in. I don't really want to start it and rev it up to 3000 to check where the timing is with it being on jack stands. This weekend weather permitting I will have it back together.
I will check and see where it is at 3000 rpm and also 2700 rpm which is where it will likely be seeing most of its WOT.
Where should the mechanical advance from the distributer be at 2700 rpm ?
I would say 34 btdc


So did you degree the cam when you installed it? :nod:
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

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Re: Whats Next

Post #21 by TeamNeptune » Tue Oct 23, 2018 5:31 pm

bubba22349 wrote:
TeamNeptune wrote:Right now my truck has the front wheels axles and gears out waiting on the carrier to come in. I don't really want to start it and rev it up to 3000 to check where the timing is with it being on jack stands. This weekend weather permitting I will have it back together.
I will check and see where it is at 3000 rpm and also 2700 rpm which is where it will likely be seeing most of its WOT.
Where should the mechanical advance from the distributer be at 2700 rpm ?
I would say 34 btdc


So did you degree the cam when you installed it? :nod:

Nope. I did not. The cam should be 4* advanced but I did not check it for accuracy.
JD

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Re: Whats Next

Post #22 by TeamNeptune » Tue Oct 23, 2018 5:45 pm

Lazy JW wrote:
TeamNeptune wrote:... out on the highway here between Charlottesville and Va Beach everybody and there grandmother will be flying by you if your doing 60mph. I can see 65mph while pulling the boat but empty, at least on the interstate I would be at 75mph...


Whee! :D

I don't remember ever having my ol' White Ox going THAT fast! :mrgreen: :shock: :lol:

You have a nice truck JW.
A friend of mine's dad has a 66 1 ton that has been parked for a while.
It has a 240 6cyl in it that supposedly was quite stout. he said his dad told him it had 2inch intake valves a 2 barrel carb and had been bored 60 over. he said the oil pump destroyed a stock oil filter from too much pressure. Thats about all I know about it at this time .
He was wanting to sell me the motor but when I heard it was bored 60 over It kind of turned me off .
Anyway thanks for the shout.

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Re: Whats Next

Post #23 by TeamNeptune » Tue Oct 30, 2018 6:33 pm

I finally got my truck back on the road this weekend. I check the timing and the dist. timing was at 10* so I bumped it up to 14* and took it out. There was some valve rattle if I got on it at around 2000 rpm in 4th gear. It had about 8gal of reg. gas already in it so I was able to get 10gal of high test at the shell station. There was a big improvement. I could hear just a little valve noise but I had to get the rpm's much lower in 4th gear and open it up on a hill.
Do you think if I ran straight high test it would help or maybe just bring it back 1 or 2 degrees ?
also on the carburetor I am thinking on getting some new plugs and running it opened up and checking the plugs.
If I ran a 1/4 mile at full throttle and check the plugs would I be able to tell if it is too lean?
Plan 2 would be to go ahead and change the jets up 1 step in the secondary and test it to see if it felt like it was bogging ..
Right now I am very happy with the improved performance with the timing combined with the 4.11 gears. :thumbup:

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Re: Whats Next

Post #24 by THE FRENCHTOWN FLYER » Wed Oct 31, 2018 5:42 pm

It sounds like what you are referring to as "valve rattle" is actually detonation. It is not really caused by valves making noise but by the volatile mixture in the cylinder igniting instantaneously, sending shock waves through all the moving parts. At least that is what I surmise if increasing octane changed the amount of the noise. In that case retarding the timing or using straight premium fuel would both be directionally correct toward eliminating the noise.

Yes, you can check main jetting by opening it up to WOT for a quarter mile or so. My suggestion would be to run it at WOT, throw it into NEUTRAL and shut the engine down as soon as possible so that the jetting reading is not masked by the mixture at idle. My good friend and fellow drag racer used to put a spare spark plug in his car along with a plug wrench. Since his wife drove the car he would have her shift to neutral after the lights and shut it down and roll to the end if the strip where she got out, exchanged the spare plug for one of the (very warm!) ones, and bring it back to the pits for him to inspect for coloration. There are lots of charts on the 'net to evaluate plug readings. My experience with modern plugs - plug technology has advanced a lot along with the rest of engine design - is that they often look to be on the lean side when jetted correctly, and heat range covers a wider range of temps.

Have fun with your truck. FTF
FORD 300 INLINE SIX - THE BEST KEPT SECRET IN DRAG RACING

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Re: Whats Next

Post #25 by TeamNeptune » Wed Oct 31, 2018 7:15 pm

I just got in from another round with the timing. The front of the crank pully is 6" 1/4 but the back half steps up and I wasn't able to get an exact measurement. I went with 6 3/8" and made the radius then marked 30* . I took a piece of metal duct tape and curved it to the radius and cut it at the 30* mark. I pulled no.1 plug and found TDC and the v notch on the crank pully and used the tape to mark 30*. I scribed it with a file and used some gear mesh paint to highlight. I disconnected the vacuum and plugged. Turned the Idle up to 2800 rpm and set the 30* mark to the first notch on the timing cover. It was difficult to see but I think it was the 4* mark. I turned the idle back to 850 and checked and it was at 12*. I hooked the vacuum back up and switched it to port vac. and went for a spin. No detonation ! I am really on the fence with the air fuel mixture gauge.
Are there any sure signs I could look for to prevent a too lean mixture from damaging my engine?
I know the consensus is the outer cylinders typically run leaner.

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Re: Whats Next

Post #26 by TeamNeptune » Wed Oct 31, 2018 7:16 pm

THE FRENCHTOWN FLYER wrote:It sounds like what you are referring to as "valve rattle" is actually detonation. It is not really caused by valves making noise but by the volatile mixture in the cylinder igniting instantaneously, sending shock waves through all the moving parts. At least that is what I surmise if increasing octane changed the amount of the noise. In that case retarding the timing or using straight premium fuel would both be directionally correct toward eliminating the noise.

Yes, you can check main jetting by opening it up to WOT for a quarter mile or so. My suggestion would be to run it at WOT, throw it into NEUTRAL and shut the engine down as soon as possible so that the jetting reading is not masked by the mixture at idle. My good friend and fellow drag racer used to put a spare spark plug in his car along with a plug wrench. Since his wife drove the car he would have her shift to neutral after the lights and shut it down and roll to the end if the strip where she got out, exchanged the spare plug for one of the (very warm!) ones, and bring it back to the pits for him to inspect for coloration. There are lots of charts on the 'net to evaluate plug readings. My experience with modern plugs - plug technology has advanced a lot along with the rest of engine design - is that they often look to be on the lean side when jetted correctly, and heat range covers a wider range of temps.

Have fun with your truck. FTF

Thank You !

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Re: Whats Next

Post #27 by TeamNeptune » Wed Oct 31, 2018 8:38 pm

pmuller9 wrote:
TeamNeptune wrote:I am still searching but last I read was with the 240 head and large cam you should be running at least 89 octane ?? I have the COMP cam 268 would this be true in my case.
JD

The Comp 268 cam has the same advertised duration as the stock cam so if you use the 240 head and raise the compression to 8.8 or more you cannot install the 268 to the cam card spec which is intake lobe center at 106 degrees ATDC without detonation.
The stock cams intake lobe center sits at 114 degrees which gives you a much lower Dynamic compression ratio that the Comp 268.

If you use one of the other brand cams like Crower or Schneider, they have advertised durations of 280 to 284 for near the same Comps .050" duration of 218 degrees.
Then you can use any grade pump gas you want with a 9:1 compression ratio.

Paul I I am trying to understand the intake event. It is my understanding that the camshafts dynamic CR will not be greater than the static CR. At a static 8.8 why would I need more than 87 octane? I do not doubt what you are saying I am just trying to understand it.
JD

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Re: Whats Next

Post #28 by pmuller9 » Wed Oct 31, 2018 9:53 pm

We know from experience from the many builds on this forum that 87 octane gas works best with a Dynamic Compression Ratio (DCR) not greater than 7:1 and a DCR of 7.5 requires 91 octane.

A Comp 268 cam installed with the intake lobe center at 106* ATDC closes the intake valve at 60* ABDC which is 8 degrees sooner than the stock cam since the stock cam's intake lobe center is at 114* ATDC.
The stock cam also has a 268* advertised duration

If the static compression ratio (SCR) is 8.4 then the DCR will be right at 7.0 with the Comp 268.
The stock cam will work comfortably with an 8.8 SCR which yields an 6.9 DCR

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Re: Whats Next

Post #29 by TeamNeptune » Thu Nov 01, 2018 5:27 am

pmuller9 wrote:We know from experience from the many builds on this forum that 87 octane gas works best with a Dynamic Compression Ratio (DCR) not greater than 7:1 and a DCR of 7.5 requires 91 octane.

A Comp 268 cam installed with the intake lobe center at 106* ATDC closes the intake valve at 60* ABDC which is 8 degrees sooner than the stock cam since the stock cam's intake lobe center is at 114* ATDC.
The stock cam also has a 268* advertised duration

If the static compression ratio (SCR) is 8.4 then the DCR will be right at 7.0 with the Comp 268.
The stock cam will work comfortably with an 8.8 SCR which yields an 6.9 DCR



Thank you Mr.Muller for your help. :thumbup:

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