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Help to stroke my AMC 150 cui Engine


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Hello after I have ascertained this my cylinder block has torn, I have laboriously procured for myself in Germany a used cylinder block.

 

Now, because I would like to make the engine new, me search tips like me the engine Performance-stronger can make. I want to remain with 4 cylinders, however, nicely drilled out and strongly.

 

Who has already made this here and can call to me tips / shopping possibilities

 

Greeting from Germany comanche.gifcomanche.gif

 

Peter

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I have researched this before and have come up with nothing. As far as I know, no one has ever stroked a 2.5L. Ive wondered if the crankshaft rod journals can be re ground off center to effectively move the stroke center outward. I know of companies doing this to stroke air cooled VW's. That would involve finding different smaller rod bearings and different length rods that will match all the new machining. Your best bet for more cc's would be to bore the cylinders to maximum overbore, and install new pistons to match. And no one currently sells a high performance camshaft for these engines either. For that, you would need to find someone who can re grind the camshaft. If you have a port injected 2.5, some larger injectors may be requiered as well. Whatever route you go, you have a lot of research ahead of you. I wish you luck, and let us know how it works out for you. Welcome to the club!

 

Edit: Just re read your signature. It appears you have a 1988 model. You have throttle body injection (That is assuming the euro models are the same as US models). You will have much more trouble getting better fueling with this setup and OEM electronics. I started to research using a GM 2 barrel TBI unit, but didnt finish. It looks like the throttle position sensors use the same voltage range, but I wonder if the OEM renix computer can handle powering two injectors.

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I have researched this before and have come up with nothing. As far as I know, no one has ever stroked a 2.5L. Ive wondered if the crankshaft rod journals can be re ground off center to effectively move the stroke center outward. I know of companies doing this to stroke air cooled VW's. That would involve finding different smaller rod bearings and different length rods that will match all the new machining. Your best bet for more cc's would be to bore the cylinders to maximum overbore, and install new pistons to match. And no one currently sells a high performance camshaft for these engines either. For that, you would need to find someone who can re grind the camshaft. If you have a port injected 2.5, some larger injectors may be requiered as well. Whatever route you go, you have a lot of research ahead of you. I wish you luck, and let us know how it works out for you. Welcome to the club!

 

Edit: Just re read your signature. It appears you have a 1988 model. You have throttle body injection (That is assuming the euro models are the same as US models). You will have much more trouble getting better fueling with this setup and OEM electronics. I started to research using a GM 2 barrel TBI unit, but didnt finish. It looks like the throttle position sensors use the same voltage range, but I wonder if the OEM renix computer can handle powering two injectors.

 

I was just reading about one, wagen.. a 2.7L. It was a fantastic read, too, even if it was just a YJ. Let me find a link.

 

http://www.jeepforum.com/forum/f12/2-7l ... ok-457885/

 

Now I face a decision. I could crate in a new motor for a couple of grand, or, now that my brother runs an automotive/machine shop, I could try to revive this one. (Addington High Performance in Atlanta, TX if any one is wondering)

 

The problem with reviving this old block is that AMC only had pistons that went 0.060” over the original bore…and I would need to bore it out further than that. Solution? 4” Chevy Flat Top Pistons.

 

We sat down with pencil and paper. The original bore was 3.88”…we’re looking at boring it out again..at least 0.030” over. 4” pistons would require 0.060” over again…giving me the 4” needed for a perfect fit. With some thought and a little guts, we decided, hey, why not?!?

 

My brother happened to be in town the next weekend, so we loaded up the short block in his car (yeah, it fit in the trunk of an old Prizm) and he hauled it back to Atlanta for the machine work. I sent the head along with it for a 3 angle valve job...

 

 

Here's the good part:

 

Major Mods:

Engine bored 0.0120” over giving 2.7L of displacement.

Floated pistons

Head ported

Pace Setter header and high flow exhaust installed

New cam and lifters, rebalanced crank and new bearings

 

Other repairs/mods:

Replaced vacuum lines

Replaces speed cable, repaired speed sensor

Fixed transfer case leak (bushing and seal, replaced yoke)

New carpet, new seat covers

Repaired steel dash under the plastic one…major rust!

Removed A/C system

Cleaned massive amounts of oil from engine compartment, intake manifold, and elsewhere

 

Future mods:

4.0 TB, possibly TB spacer

High flow intake

Possibly roller rockers

Possibly electric fan

 

All told, it ran me around $400 bucks.

 

Dyno thread:

 

http://www.jeepforum.com/forum/f12/back ... er-481639/

 

That said, I think that in Euroland, this wouldn't be something I would attempt, unless you had the same type of resources (machine shop/racing engine background).

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