I just ordered the 350 caproce motor and i see that a couple of you have this engine but have replaced the heads. whats the differance in these heads and the stock 91 5.7 heads

 

I replaced my heads, not because they were bad, but becuse I bought the long block for a base to work with. I bought the long block and sold the heads to my friend which brought my price down to what they were asking for a short block and my friend got NEW GM heads for the price of rebuilds. Plus I needed the oil pump & pickup, roller lifters/retainers/spider, oil pan, valve covers, misc bolts, etc, since I was converting to a newer engine style than my 85 engine. So it was the most economical thing for me to do. The heads are probably pretty compatible to what came in the L98s.


James

 

i think they are extremely close to the stock heads. i know the tpi bolts right up. i have this motor on my car. i had to use my old timing pointer though.

 

I guess I'll metion some things as well.


* There is a sensor hole in the oil pan that needs to be plugged. It is for an oil probe on the caprice. So either plug it or get the probe and bolt it on. It won't hurt.

* The timing pointer and dampner have the 12:00 timing positions. if you have TPI you will need to:

A) reuse your existing timing cover and dampner

B) Reuse your dampner and get an aftermarket timing pointer. Pep boys has a chrome one for $5.

I ended up getting an 8" (for a 1985 G-20 vanw/350) dampner and the chrome Mr Gasket pointer. I check TDC when I had the heads off and the pointer, to my amazement was dead on.

I actually thought the stock heads looked pretty decent. I just wanted something more than just a stock L98. The guy that went 15s did so because of major tire spin, which I can beleive because of the cam that cam in it and the nature of TPI.

That's about it. No major or minor concerns beyond that. However the engine I got from Scoggin-Dickey had some dirt/debris on the engine that needed to get cleaned off.


James

 

I'm one who used the Caprice engine - it was a good move, for me. I would venture to say that the long block is the same as the L98. I didn't measure the cam spec's, though, since I intended to swap it out, anyway (and did). I think the real difference between the L98 and the L05 is the induction system. The L05 is TBI, whereas the L98 is TPI - big difference. I think the compression ratio on the L05 is actually slightly higher than on the L98. If you're looking for a "stock" replacement and the cam turns out to be "the same", the Caprice engine is the way to go. Again, beware of the '87-up intake bolt angles...

It's not a real fair comparison because I'm running a mild cam and Edelbrock heads, but my engine's noticeably stronger than the original L98 it replaced.

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'87 IROC 5.7l TPI - original owner!

 

my is a 91 so the intake will bolt up and i plan on changing cams. i just wanted to make sure that the heads dont suck. thanks all.

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91 Z28 slp headers adj reg accell cap rotor coil comp cam roller
random tech cats flowmaster catback

 

Half the ports suck, the other half blow. The question is how well



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'87 IROC 5.7l TPI - original owner!