anyone ever herd of forged aluminum? i was looking for a set of pistons when i bore my block.
http://cgi.ebay.com/ebaymotors/Pisto...QQcmdZViewItem
anyone know what kind of comp ratio il be getting. my heads are votrecs with 64cc chambers, i could always go smaller. any ideas?

 

Generally if your running forced induction or nitrous you want to run forged pistons since they will stand up to a bit more detonation than a cast piston. Which could really save your ****!

Typically a basic rebuild would use cast pistons to save the cost as a 'run of the mill' street motor wouldnt be so succeptable to detonation.


Couldnt tell you the compression ratio unless i had the TRW part number or the actual cc's the valve releifs come out to.




Also, you should have the block punched out BEFORE you get the pistons! You never know, the block might already be .030 over or it could be a std bore but they might have to take it out to .040 or something!


If your interested int hem, get the part number from the seller and refer to this page for an ESTIMATED compression ratio.

http://www.flatlanderracing.com/trwchevy350.html

Im going to go out on a limb here and say those are the pistons that will put you in the 9.5-10:1 CR area...

 

I'd say bring the block to a machine shop, and ask what overbore is needed, then tell them you're going to go buy the pistons.

He'll measure it, and say ".030" or something like that, then you can buy the pistons, and bring it to the machine shop so he can bore and finish hone the block for those pistons. He'll want the pistons in hand before he bores it out, or else he'll have to bolt it up to the fixture again to finish hone them, and that'll cost you more again.

you basically got 3 choices for piston-

cast - stock rebuild
hypereutectic (cast, but higher silicon content, better) - Pretty much everything else
forged - forced induction or VERY high performance naturally aspirated

Always aluminum.

And yea, I agree with 84z, 9.5-10:1

 

Before you purchase pistons, have the block bored. Your engine / machinist will tell you the correct size to order. He'll also be able to help you with the selection based on the intended use.

Good luck