a new "blow-through" build..

that sounds like a Tillotson carb used on snowmobiles in the 70's and weedwackers and the like up to this day. no float bowl just a vacuum pulse fuel pump mounted to the side.
 
country fried 6":9lo8gz0c said:
that sounds like a Tillotson carb used on snowmobiles in the 70's and weedwackers and the like up to this day. no float bowl just a vacuum pulse fuel pump mounted to the side.

that sound right..shall we say "simple"?..of course those 470's and later 520s were very low RPM sixes..with massive bore though..(by comparison), but still pretty OLD SCHOOL..
 
johns3524":2k7eh3oz said:
pmuller9":2k7eh3oz said:
I was thinking about the possibility of using mechanical fuel injection where you can manually control the main and secondary bypass and have full control of the fuel. No carb and the problem of boost referenced fuel pressure goes away.
Just a thought.

Something to think about..and read up on of course..I'm sure they've made some advances since inception years ago..and since we're reading how about this?

https://en.wikipedia.org/wiki/Pressure_carburetor

AND: https://en.wikipedia.org/wiki/Bendix-Stromberg_pressure_carburetor

ps5 style actually ebay has a cple that were used on O470CI continentals in the 50-60s 230HP...well, more thinking I know.

I have decided to buy the leaning device from the maker as soon as he can ship, and try it on one of my Holley's' on the DD I have now. that may tell me if that type of thing is workable..

Looks like barometric controlled mechanical throttle body fuel injection. Thanks for the links. Good stuff.

There seemed to be a lot of advances in piston engine tech up to the end of WWII. 4 valve heads roller valve trains ect... Then we kinda took a few steps backwards for a while.

Here is a link to someone that has a lot of miles with their converted Holley 2300.

http://www.binderplanet.com/forums/show ... stcount=14
http://www.binderplanet.com/forums/show ... stcount=16
 
pmuller9":3bkipmwc said:
johns3524":3bkipmwc said:
pmuller9":3bkipmwc said:
I was thinking about the possibility of using mechanical fuel injection where you can manually control the main and secondary bypass and have full control of the fuel. No carb and the problem of boost referenced fuel pressure goes away.
Just a thought.

Something to think about..and read up on of course..I'm sure they've made some advances since inception years ago..and since we're reading how about this?

https://en.wikipedia.org/wiki/Pressure_carburetor

AND: https://en.wikipedia.org/wiki/Bendix-Stromberg_pressure_carburetor

ps5 style actually ebay has a cple that were used on O470CI continentals in the 50-60s 230HP...well, more thinking I know.

I have decided to buy the leaning device from the maker as soon as he can ship, and try it on one of my Holley's' on the DD I have now. that may tell me if that type of thing is workable..

Looks like barometric controlled mechanical throttle body fuel injection. Thanks for the links. Good stuff.

There seemed to be a lot of advances in piston engine tech up to the end of WWII. 4 valve heads roller valve trains ect... Then we kinda took a few steps backwards for a while.

Here is a link to someone that has a lot of miles with their converted Holley 2300.

http://www.binderplanet.com/forums/show ... stcount=14
http://www.binderplanet.com/forums/show ... stcount=16

good input..I notice that that posting talks about a different approach as the one I'm considering but good to look at none the less.

The Percy adjust a-jet ..

I have the hope that the Device I'm looking at is a complete adjust form idle-cutoff to full rich with a lever..not an adjustment screw..we'll see.
 
johns3524":wpggd02i said:
good input..I notice that that posting talks about a different approach as the one I'm considering but good to look at none the less.

The Percy adjust a-jet ..

I have the hope that the Device I'm looking at is a complete adjust form idle-cutoff to full rich with a lever..not an adjustment screw..we'll see.
He was using the Percy Adjust-a-jet.
He connected a cable to the adjustment screws so adjustments could be made from the driver.

What would be different?
 
pmuller9":1hz45tbw said:
johns3524":1hz45tbw said:
good input..I notice that that posting talks about a different approach as the one I'm considering but good to look at none the less.

The Percy adjust a-jet ..

I have the hope that the Device I'm looking at is a complete adjust form idle-cutoff to full rich with a lever..not an adjustment screw..we'll see.
He was using the Percy Adjust-a-jet.
He connected a cable to the adjustment screws so adjustments could be made from the driver.

What would be different?

This device is actually a full range from idle-cutoff, or full lean to full rich (at least as advertized). It has a lever on the SIDE of the block that will hook directly to an aircraft style McFarland or other mfg 's vernier cable.

http://www.mcfarlane-aviation.com/Products/?PartNumber=MC600-72

http://www.rotaryeng.net/HOW-TO-INSTALL-HOLLEY.html

I must admit I've only been in-touch via-e-mail. I probably should reserve judgement till I actually view it in my hand.
 
johns3524":2sa98sp5 said:
This device is actually a full range from idle-cutoff, or full lean to full rich (at least as advertized). It has a lever on the SIDE of the block that will hook directly to an aircraft style McFarland or other mfg 's vernier cable.

http://www.mcfarlane-aviation.com/Products/?PartNumber=MC600-72

http://www.rotaryeng.net/HOW-TO-INSTALL-HOLLEY.html

I must admit I've only been in-touch via-e-mail. I probably should reserve judgement till I actually view it in my hand.

This is really cool stuff that I didn't know was available.

The Mcfarlane unit has a 90* turn from off to full rich. That seems to be a little coarse making it hard to make very small adjustments but like you said, wait until the unit is in your hands.

Which Holley carb will you be testing this on?
 
pmuller9":lco8lp9w said:
johns3524":lco8lp9w said:
This device is actually a full range from idle-cutoff, or full lean to full rich (at least as advertized). It has a lever on the SIDE of the block that will hook directly to an aircraft style McFarland or other mfg 's vernier cable.

http://www.mcfarlane-aviation.com/Products/?PartNumber=MC600-72

http://www.rotaryeng.net/HOW-TO-INSTALL-HOLLEY.html

I must admit I've only been in-touch via-e-mail. I probably should reserve judgement till I actually view it in my hand.

This is really cool stuff that I didn't know was available.

The Mcfarlane unit has a 90* turn from off to full rich. That seems to be a little coarse making it hard to make very small adjustments but like you said, wait until the unit is in your hands.

Which Holley carb will you be testing this on?

Actually I'll probably try it first on a 4 barrel Holley to see what kind of flow is available then on a 2 barrel for full install. It could be used on a 4 barrel (I have a couple of spares) though for sure if it's usable at all. Right now I don't have a 2300 Holley, or a 4 barrel adapter for my Clifford intake but I could make one up.

The McDonald Vernier adjustment is like the control knobs on any airplane that is used for three functions or at least two on a small plane...throttle, mixture, and prop adjustments (if the plane has a governed constant-speed prop installed)

They will work as a pull type of cable, or micro-adjust by twisting them left(out) or right (in). When you want full release of control you "push" on the button in the middle to release the cable for full push in. You CAN also pull it out and push it in you depress the button on the knob. This has been common for many years. The middle button is like a lock for the position ur twisted (adjusted) to.

This way you micro-adjust but twisting left or right which uses threads to control small increments of pull or push. You can "dial'm in as you wish.

In actual use, all controls are "pulled" out at shutdown except the prop control (it is parked at "full rpms" generally because the prop was "pushed in" on final approach in preparation for a go-around if needed)..
Throttle OUT at idle, mixture OUT with fuel at idle-cutoff (full lean). On start, the mixture full rich (in) engage starter with hand on throttle for cold idle firing and adjust. On takeoff roll. mixture "in" (full rich), prop (if equipped) full "in" (full rpm), throttle "in" (full power/manifold pressure)..When pushing all in...press center of knob with palm..and "firewall it"...In a truck/car you could use a vernier control cable for a poor man's cruise control...

let's see, throttle(cruise), mixture, spark adv, boost (4)..+choke all different colors/sizes (to find in low light)..that's the knobs...then go to the gauges....
 
I actually like the the lower pressure approach of the "draw thru" of "can this work".....makes it all even simpler..and my other controls work as well..less fabbing.. no inter-cooler..and I am familiar with draw thru..well..need to get an engine built first..
 
johns3524":1xg4tyx3 said:
I actually like the the lower pressure approach of the "draw thru" of "can this work".....makes it all even simpler..and my other controls work as well..less fabbing.. no inter-cooler..and I am familiar with draw thru..well..need to get an engine built first..

There are reasons why you see mainly “blow thru” carburetor setups for turbo applications rather than “draw thru”
and the lack of “draw thru" systems have very little to do with the present day use of EFI.

There are 2 air pumps in the system, the turbocharger and the engine.
The engine determines the linear airflow (as in cfm) between it and the turbo.
It is mainly a function of engine displacement, engine rpm and the volumetric efficiency at a given rpm.

The turbo controls the airflow coming into the compressor.
Inlet airflow is a function of the outlet flow multiplied by the pressure ratio or boost level.

Just for clarification the engine sees more air by weight after being compressed by the turbo but the airflow is still close to the same by volume flow.
The engine still pumps ½ of its displacement x rpm x VE the difference being the air is more dense.

If you place a carb after the turbo on the intake manifold it still gets sized about the same as if the engine was NA since the flow is about the same.

However the airflow on inlet side of the turbo compressor is proportional to the outlet flow (engine airflow) multiplied by the pressure ratio or boost.

This means that a carb that is specified for the engine at zero boost needs to increase in size as the boost increases.

Let’s look at your specific engine project at 3500 rpm.

At zero boost and a VE of 80% the engine airflow is about 250 cfm and the turbo inlet airflow is about the same
A 350 cfm 2bbl or a 390 4bbl would work fine.

At 10psi of boost and an intercooler with 60% efficiency, the turbo inlet airflow has jumped to 400 cfm.
In this case a 500 to 600 cfm carb would be needed for a “draw thru” set-up while the “blow thru” would still only need the 350 to 400 cfm carb.

If the goal is a low rpm high torque engine the larger carb set-up is not optimum.

Second: Any restriction on the inlet side of the turbo decreases the turbo’s output.
The turbo multiplies the inlet pressure to produce the outlet pressure.
If you reduce the inlet pressure by traveling to "Mile High" Denver or stuffing a carb in front of it, the output will be reduced.
If you drive the turbo harder to regain a particular output level the outlet air temp will be higher than before.

Third: If a small carb is used for a “draw thru” the turbo could be forced into a surge cycle as the boost climbs beyond a certain point causing possible damage
same as using too big of a turbo for a particular engine size. I’ve had that happen once.

Intercooling: Most air to air intercoolers have at least a 60% efficiency.

In your case the turbo outlet temps will be at least 200*F @ 10 psi of boost @ 3500 rpm using an outside air temp of 75*F.
With a 60% intercooler the engine intake temps will be 130* and the engine torque shows as 425 ft.lbs

Without an intercooler the engine intake air temp will be that 200*
The engine torque decreases to 375 ft.lbs and the chance of detonation will increase a lot.
If you have to pull the timing back to prevent detonation then the engine torque will decrease even more.

Hope this is helpful
 
pmuller9":1eg1jtkb said:
There are reasons why you see mainly “blow thru” carburetor setups for turbo applications rather than “draw thru” ......detonation then the engine torque will decrease even more.
Hope this is helpful

Yes very helpful. I should admit that I'm not seriously thing about a "draw-thru" arrangement..it was one of those times of thinking out loud while typing and I pressed "enter"...but it was too late. And, I DO plan to have an inter-cooler.

I really hoping to hear back soon from the guy with the leaning device. It has me concerned that I can't get him on the phone at this point too see what his schedule is. But I need to focus on cleaning up my small "shop" for this project anyway getting some other things done and out of the way. I think I'll assemble that .060 over block and pistons to get it off my stand, and put it away for now.

BTW, here's another question for ya...

Have you seen a gauge that can measure and display degrees of advance BTDC live in real time INSIDE THE CAB? You'd think someone would build that into a tach readout...

Well I appreciate the input for sure, and wish you well on your 240 endeavor..keep the faith...and..
"keep those cards and letters comin' in"
 
pmuller9":38qs91zl said:
johns3524":38qs91zl said:
BTW, here's another question for ya...
Have you seen a gauge that can measure and display degrees of advance BTDC live in real time INSIDE THE CAB? You'd think someone would build that into a tach readout...

I haven't use it but here is one

https://dl.dropboxusercontent.com/u/39382077/dsg1401brochure.pdf

Good morning..
That looks like a sturdy unit, thanks for the link. I.m going to give that some thought when I'm actally workin on the block.
Another question I've pondered over is the oil-drain-back. (turbo). While looking at other blocks for turbos, I've noticed that some actually have tapped some threads in the passenger side block for an AN fitting...have you ever thought about that? Some might wonder why you would actually put a hole in you block on purpose I suppose when a welded up oil pan would do the job.

Another thing I've been thinking about is using the HD exh manifold that Stevens sells. And since this IS a ground-up turbo build, why not use the stock log?

Doing both of those things might be a space saver, in addition to being unique. I just have to get comfortable machining that intake for a good seal for a 2 barrel..thoughts?

If I use the standard heating method for the intake, it makes it easier to not use the heater in the summertime, although I could do an exotic shutoff valve arrangement I suppose...

Lets have a good week...and hopefully not an icy one ;;

JS
 
johns3524":305vofid said:
pmuller9":305vofid said:
johns3524":305vofid said:
BTW, here's another question for ya...
Have you seen a gauge that can measure and display degrees of advance BTDC live in real time INSIDE THE CAB? You'd think someone would build that into a tach readout...

I haven't use it but here is one

https://dl.dropboxusercontent.com/u/39382077/dsg1401brochure.pdf

Another thing I've been thinking about is using the HD exh manifold that Stevens sells. And since this IS a ground-up turbo build, why not use the stock log? (intake) Doing both of those things might be a space saver, in addition to being unique. I just have to get comfortable machining that intake for a good seal for a 2 barrel..thoughts?...

Having said this, I DO realize that some performance may suffer as a result..just wondering how much..
 
I don't think you could machine the stock intake enough to gain any performance over just using a 2V to 1V adapter. However if your comfortable welding cast iron you could slice the 1 V center section out (carb base) and build a 2 V center out of steel plate or tubing to replace it. From my A&P mechanic training I do like your ideas on being able to adjust timing and fuel mix from the cab, good luck on your build :nod:
 
bubba22349":2xiq4kuf said:
I don't think you could machine the stock intake enough to gain any performance over just using a 2V to 1V adapter. However if your comfortable welding cast iron you could slice the 1 V center section out (carb base) and build a 2 V center out of steel plate or tubing to replace it. From my A&P mechanic training I do like your ideas on being able to adjust timing and fuel mix from the cab, good luck on your build :nod:

Thanks 4 the input bubba, I actually have been interested in one of those adapters. Abut that, have you noticed that the add for those on Mike's site doesn't seem to show the correct orientation? I'd like to see one that is specific to a 300 and see what it looked like. I think I'd order one just to have it.

Thanks again for the comments..and about fuel mix/timing from inside while "flying", for me it is what would make this project work..I hope the guy gets back to me soon about the carb leaning device...that piece of info is very important to me at this point.
 
bubba22349":mp02j253 said:
I don't think you could machine the stock intake enough to gain any performance over just using a 2V to 1V adapter. However if your comfortable welding cast iron you could slice the 1 V center section out (carb base) and build a 2 V center out of steel plate or tubing to replace it. From my A&P mechanic training I do like your ideas on being able to adjust timing and fuel mix from the cab, good luck on your build :nod:

With some further "thinking"..I really wonder if just using a Clifford with a water heater is probably a good approach. Other than being bigger and more in the way while trying to fit it in the engine bay, it DOES do a pretty good job of heating and balanced COOLIng of the intake with it's water approach. I guess we'll see what I end up doing about that problem.
 
Bubba made a point that the 1V center section of the stock manifold is a bottle neck and would be a restriction unless it was modified. I would have to agree.

Aftermarket aluminum intakes have larger runners for upper rpm performance and are not ideal for this project.
Having said that, the manifold just bolts on and you're done. The turbo will warm the air under boost but it still may need some heat in the manifold when cruising on cold days when there is no boost.
I like your idea of a simple water shut off valve. You need another control cable in the cab. LOL

I would also take a close look at the bottom half of the stock EFI manifold. It had long equal length runners that have small cross sectional areas.
You could fabricate a log that would bolt to it that would accommodate either a 2bbl or 4bbl carb.

The HD exhaust manifold may not flow quite as well as the EFI but it sure makes tha turbo installation much easier.
I would be inclined to use it. The turbo can bolt to the manifold flange by way of a simple adapter and there would be very little heat loss to drive the turbo.

We always used the oil pan for the turbo oil return. You can weld on any size AN fitting you need to minimize oil return restriction.
 
Thanks to both of you above posters this am. I think I have come to a decision about what parts to start collecting regarding the intake exhaust situation. I will order the following soon.

1. A new HD exhaust manifold from Steven Parts (talked to him this am)
2. A new 2>1 adapter from Classic Inline s. I talked to "Mike" this am and he said the orientation is right and they are now in stock.
3. A new Holley carb style leaning device (hopefully he will get in shipping mode soon)
4. A new method of manually adjusting advance applied to a standard re-curved diz. (workin on that and will take up pmullers help in that process likely)

As I already have tow (2) standard intake manifolds, I should be able to fit one up to utilize a Holley 2300 and also the hot-air heating of the standard HD exh. This will at least let me fab up all of the other stuff I need to get underway and leaves room to modify it all as I go should I want to tear open an intake log and mod it as discussed for an improvement. At least it will be drivable with all of the other controls I want to test..and it can only benefit by improvement as it goes. right?

Oh, and I forgot..I most likely WILL poke a hole in the oil pan for the oil drain..and use a big-OL AN line...

I should be able to get this built and installed on my engine stand for breaking in without too much trouble and then deal with the inter-cooler install in the vehicle. Thanks all for patience..I have a lot of work to do..and budgeting as well. and some shoppe cleaning..before I even have the room..

As I have mentioned in a post or two B4, to sum up at the risk of being redundant, (redundancy..a condition that many "experienced" in life succumb to as a result of forgetting what they have already said), I merely want to be able to drive this inline 6 along with little or no trouble while being able all the while to constantly and successfully add and monitor the use of...

"a'little bit of throttle,... a'little bit of mixture...a'little bit timing...a'little bitof bbbbbbbbbbooooooooost..." OOPPS!.. this could be a tune..if put together (tuned) properly....
 
Hey there..I may be missing a button..or some feature..or ??

I have sent a that's still in my OUTBOX. WHO sends these?...I can't find anything in FAQ's, so forgive me if I'm a newbie...but how does one send a PM..must it be recvd by the party b4 it goes?...anyway..If anyone will inform me of the protocol..I'd be obliged..I ..enlighten me...

Edit:...now I've got it...

Thank you all.
 
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