ok, As some of you probably know, i have a blown 305 TPI in my 1987 IROC-Z, I will be putting a 87-newer 350 small block in with what ever heads it comes with, maybe I will port them, use the same cam I have now (L98 right..in 305 5-speed). A Summit rebuild kit. I think I will go with Fordged or the Hyper-I-can't-spell-or-say-it's-name Pistons. I will not be blowing this engine, I will have a vortec RJ on top tho next summer so I was wondering, should I get the Summit Cast,Forged or Hyper-bla-bla-bla pistons? The Forged are cheaper then the hyper-you-know-what pistons. Also any recomendations on what to look for in a junkyard block? I was thinkin' I should take off the oil pan at least and maybe the heads or somthing to look at the top end. 350s are about $225 around here. If you a looking for one search for 'Junkyards' @ ask.com and click on Junkyrd dog or something. It is a nation wide listing, just watch out it is an old one and some area codes have changes.

[This message has been edited by camaro6spd (edited June 21, 2001).]

 

I don't think I will be adding nitrous, What do you guys think about the cast kit for 279.95 vs the fordged kit for TRW 386.95 or with Keith Black Hypereutectic Pistons for 398.95. Just remember I am trying to get the IROC to look right too. Did they come stock with cast and would they hold up to 350hp??

-Tom

 

It came stock with the hyper pistons. I would recommend hyper replacements if you don't plan on serious nitrous. (A little 75 or under shot on hypers is OK in my book)

Forged pistons run with excessive wall clearence so the bang and slap around in the bores until the motor warms up. Sure there are 'tight' fit forgings available now but the price is crazy on them. Your rings will last longer with less piston rocking and the 1/16" rings wear faster than the hypers 5/64".

But. At high rpm, 6500rpm or better, the 1/16 rings will seal better plus they have less drag.

Hypers sound like a better choice for your app. They could withstand the hp no prob, even more...

 

thanks
what are cast useful for, just some guy rebuilding the stock motor so it will run?

 

cast are for paperweights in offices, somewhere along the line a moron mistakenly said they should go in engines.

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• 83 Z28-- not a pretty site to look at, 200k miles and im sure it was treated like a rental car every day of its sad life(before i got it).. sold, thank the lord
• 74 Z28-- 383/400, green on black. pretty clean. FOR SALE!!!

 

ok, I decided to take the Summit rebuild kit w/o pistons for 224.95 and add Federal Mogul Hypers ( both for .030 over) and I get a price of 328.91. Not bad seeing the summit price for the hypers is 398.99 but they have keith black any difference that makes it worth the extra money?? Also with the FM Hypers it gives me the stock 9.35 compression, I want to bring the compression up so that i can run somewhere inbetween middle and high test gas. What CP are we looking at here and can I obtain it buy having the heads and bloacked decked??
Thanks
Sorry for the long posts it is I am just now getting into the meat of the project.

 

Jegs sells Speed Pro Hypers with a .125" dome and an anti-friction skirt coating for about $26 a hole.

This may be boostin' a little much. They claim 10.68:1 CR with 64cc chambers.

I plan on grinding a notch right under the spark plug electrode to help flame travel and also to drop the CR just a hair.

Another way is to get 'claimer' pistons. These usually have two valve reliefs or a single trough relief instead of 4 valve reliefs. I never understood why they put 4 reliefs in a piston when there's only 2 in each cylinder. The extra surface 'roughage' can't be all that good for cumbustion properties IMO...