I am thinking about building a small block for my 92 formula and I had a few combinations in mine, but first I have a few questions. First off, what is the max a 350 can be punched out to safely? Second I am debating if a supersharger is going to be an addition so what is reccomended for compression with a super charger? Also, who makes decent lightweight internals??

 

I wouldnt bore a 350 anymore than 60 over unless you want major problems. Superchargers dont need globs of compression so with a 350 don't run flat-tops pistons and try to stay below 9.0to1 compression.

On the same note, machining any motor for larger pistions raises compression.

 

engines should be bored only enough to clean up the cylinder walls, you would feel no difference in peformance between a 4.000 inch bore and a 4.060 bore.

 

If you are absolutely sure that you are going with a supercharger, then build it with 8.5:1 compression ratio. If you have a used 350 block, just go 30 over (4.030" bore). This will force you to buy new pistons. And while you are at it, you best buy a forged crank due to the supercharger, so you might as well build a 383. There are plenty of good engine parts for a 383 build and several manufacturers of these parts.

BTW: not all 350 blocks can be bored out to 60 over; most maybe but not all. That is why two of us are recommending 30 over.

When I built my 395 cu.in. stroker, I did alot of research on the matter. Do alot of searches and bookmark the engine component sites that you find. Also, buy a couple engine build-up books. The most important component that you are going to buy is the crankshaft. I went with the forged Callies Dragon Slayer. I think that its the best forged crank for the money. Well, thats my 2 cents worth.

 

Doc, not at all recomending a .060 overbore....just if it has to go to that much of an extreme anything over .060 might as well be thrown away.

I agree that .030 over is not only reletively standard but safe and would never recommend a motor be cut anymore unless it absolutely had to be.

 

Jay: Please dont take me wrong here. I was not coming out here for a fight. I guess we do agree that 30 over is common place and well recommended for a "safe" over bore amount.

 

I had a .060 over motor that lasted for about 3k miles in a buddy's ride, I got it and it and rehoned it and as soon as I drove ita round the block, one of the bores cracked.

If you can get away with it, punch .010 over. There's no need to use up a block that way. The more meat you leave in the bores the more rebuilds that block can take.





And this was a nice 4-bolt block from a 72 Chevelle I think. Probably superstitiously regarded as a "desirable" casting. Didnt do much for me except cost me a bunch of money.

 

Hey thanks gents. I appreciate all the info. WHat are some good books to read?

 

Chevy High performance Engine Assembly Guide by Alex Walordy.
and
How to rebuild Your Small-Block Chevy by David Vizard (HPBOOKS)