The Ultimate IH Fourbanger

The ultrasonic thickness tester was returned to the machine shop a few days ago, so at the last minute, the boys also did a cursory scan of the block for me, they like the looks of it and see no problem in handling whatever over-bore we wanna go with. No charge for that as it wasn't on the workorder and they did not do a full-on test.

What did they get for a minimum wall thickness... Needs to be at least .250 (perfer closer to .300) to take the bore we are planning...

I have mine and have tested its accuracy. Made some sensor head adjustments to work well on the id of a cylinder... I am seeing +/- .005 regularly on a known cylinder
 
I sounded my block and it is ok..

All major thrust faces are .3125 (5/16) +

minor thrust faces are .295 +

perpendicular to the thrust faces on the thinnest side of the thinnest bore. , is .240.

All of the others are .260 + thinnest perpendicular to the thrust face.
 
what did they get for a minimum wall thickness... Needs to be at least .250 (perfer closer to .300) to take the bore we are planning...

I have mine and have tested its accuracy. Made some sensor head adjustments to work well on the id of a cylinder... I am seeing +/- .005 regularly on a known cylinder

The guys just did a quickee on a few cylinders, nothing definitive really as it was an afterthought and free! I told 'em I was lookin' to make them bores paper thin for weight reduction, so they said we could drill 'em away!

We'll do the definitive thickness thing when we ream the holes out after selecting the piston design and size.

Regarding the new tool...what happens if ya shoot say a water jacket from the exterior, where there is say a space of 3/8" behind the wall and then another wall? Does the instrument read cumulative thickness or can ya read only the single thickness?

Reason I ask...I'd like to be able to determine where the casting/water jackets start and stop on these aluminum intake manifolds so I can "locate" the machine work for the carb mount flange mod.
 
Regarding the new tool...what happens if ya shoot say a water jacket from the exterior, where there is say a space of 3/8" behind the wall and then another wall? Does the instrument read cumulative thickness or can ya read only the single thickness?

Reason I ask...I'd like to be able to determine where the casting/water jackets start and stop on these aluminum intake manifolds so I can "locate" the machine work for the carb mount flange mod.

It only reads a single continuous thickness. An air space would cause the reflection it reads.
 
Any updates on the build?

I am at the point of getting ready to pull my motor and trying to decide how to go with the build. I am really interested in how this turns out and if it will be doable for me and my budget. And ofcourse what the final output numbers look like.

Craig
 
UPDATE!!

Been busy but managed to cnc my intake manifold flange out of 3/4"thick crs. Figured I'd do away with the gasket and machined o-ring grooves. Hi temp silicone o-rings will last practically for ever given proper crush.

This will go on the 152 ( note the trapezoidal port for the 152 ) that is in my Scout now with dual side draft delorto dhla 40h's being force fed by a garrett gt series turbo. I went only big enough to allow for the 200 hp at it should make @ 4500 yet ensure a very quick spool up and very little lag. The turbo is good for 270 hp max gas flow so I have a conservative margin.

The other flange is for the exhaust and is cnc'd from 1/2" thick 304 stainless. Made a couple of extras for the next engine.

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Moving along with parts. The carb flange is finished and should be fine. Cut for 1 5/8 od tubing. I can't wait to try it out.

Carbs are dhla 40-h's the h is a designator for units that are spec on a lotus turbo esprit. That was a blow through turbo charged application as well. They have all necessary enrichment metering and other components to take up to 2 bar or 30# added manifold pressure.

Plan is to get stock rolling road power numbers and then the same but with the duals. Lastly with the turbo and duals. I do expect 180 hp +/- a touch corrected for altitude and ambient conditions at the crank @ 10 pounds.

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moving along with parts. The carb flange is finished and should be fine. Cut for 1 5/8 od tubing. I can't wait to try it out.

Carbs are dhla 40-h's the h is a designator for units that are spec on a lotus turbo esprit. That was a blow through turbo charged application as well. They have all necessary enrichment metering and other components to take up to 2 bar or 30# added manifold pressure.

Plan is to get stock rolling road power numbers and then the same but with the duals. Lastly with the turbo and duals. I do expect 180 hp +/- a touch corrected for altitude and ambient conditions at the crank @ 10 pounds.

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Sexy!! Now you have to get this thing done! With bling like that I am dieing to see what it puts out!:yikes:
 
Is your plan to use one barrel per cylinder with no plenum or mixing chamber, just straight tubes from each barrel to a single cylinder? Flanges look great and the o-rings on the manifold are very cool-nice touch.
 
is your plan to use one barrel per cylinder with no plenum or mixing chamber, just straight tubes from each barrel to a single cylinder? Flanges look great and the o-rings on the manifold are very cool-nice touch.

Yes, one barrel per cylinder. This type of induction system is very effective at making a strong torque curve because of the high intake pulse strength. Also makes great low/mid range torque and power not possible in a common plenum design.

My plan currently is a long 16" j shaped runner to maximise low end torque. Like the late model tuned intake systems in use today.

The carbs inlet will face toward the engine flowing outward and making a turn back to the head. If it doesn't work well as planned I can cut it apart and redo with a short traditional runner.

But it is still a work in progress in my haid so it May change. :crazy:
 
So you envision the carbs sitting almost over the cylinder head? Up high above the engine exhaust, it should keep the air/fuel cooler as well. The "j" is supposed to disrupt laminar flow forcing the gas to mix more completely as it flows to the chamber?
 
so you envision the carbs sitting almost over the cylinder head? Up high above the engine exhaust, it should keep the air/fuel cooler as well. The "j" is supposed to disrupt laminar flow forcing the gas to mix more completely as it flows to the chamber?

All on the hardware will live on the drivers side.
The j is only to fit the long runner with in the left side on the engine compartment. The long runner has a lower resonant frequency thus will present the static pressure wave to the intake valve at a lower rpm. This in return makes higher ve and cylinder pressure and torque at hopfully the rpm where the cam makes the best torque. I can only get close as the runner legnth that posesses the proper resonant q is something like 28" long.

These unknowns are my primary reason to go with the orings. Once it is debugged my next one will probably use the standard gasket.
 
My stoker engine project is still in progress. I'm continually adding parts to the pile for the full assembly.

The engine that is in the vehicle will come out and go on a test stand soon, I gotta have one running for doing carb and ignition work so the old 196 is going to be a forever test motor.

I don't know Robert's situation at this point.
 
Yes and no. :icon_rotate:

yes in that I know what I am going to do for sure just need to source the parts. No in that I sold my 196 crank doner engine to a needy individule.

Now I only need to take my 152 crank down and see how far my crank guy will weld and stroke it. To much welding heat and it will look like a pretzle.
I'm looking for almost square bore to stroke. So 3.875 - 3.900 will do.

Never enough time.
 
Hey, I know how that goes. I'm glad you're still working on it though, hate to see such a neat project get abandoned. Supposing you can get the crank stroked that far, do you have some off-the-shelf pistons and rods picked out for the engine?

Oh and is yours an early contour head? Kinda looked like it when I was leafing back through the early pages of the thread.
 
I do have some off of the shelf options but depending on achievable stroke the piston will be different. The rod May very possibly be a custom piece. Or a bbc unit if the crank will allow it.
The current 152 is a contoured piston type but that will change to a 345e head and flat top pistons at around a 4" bore.
 
I'm really interested to hear how far your crank guy thinks he can take the crank.. I've got a spare 152 at home that is going to get stroked "someday". Seems like the crank welding and grinding is a pretty unavoidable expense in a project like this, so I've been thinking maybe the best way to keep cost down is to grind it so you can use off-the-shelf parts in the rest of the build.. This is all purely armchair wrenching since I'm 1000 miles away from the engine at college.
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Total cost for pistons and rods done this way is around 300 bucks.. (using silvolite 1278 pistons and eagle 6123 rods) course its pretty far under the displacement you are shooting for. Just thought I'd share the idea in case anyone on a tighter budget is reading along.
 
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