Thread: need help identifying postons

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Originally Posted by techinspector1

I see you're asking the same thing on Camaros.net and have released additional info that we don't have, such as the pop-up being 0.427" tall. These pistons will make about 14:1 static compression ratio with your 64cc heads, so plan on using racing gas, E85, methanol or ethanol.
If you plan to operate the motor on pump gas, you need pistons with a 12cc dish to mate up with your 64cc heads, making about 9.6:1 static compression ratio. Assuming you have a stock block deck height, (~9.025"), use pistons having a 1.560" compression height or a couple thousandths taller and use a steel shim head gasket (0.016" - 0.020") to tighten up the squish. You'll want to check the flatness of the block and heads before you use the shim gaskets.
https://www.youtube.com/watch?v=u4SzK_OjAkY

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thanks, i haven't posted any where else. After posting here last night i did some more research and found a post similar to mine. 14:1 definitely would not work for what I want to do. The same guy i got the heads from has a set of forged dished pistons he will let go for 60 bucks. My target static cr is 10.50:1 i figured a set of domed pistons would work and might save me money in machine work in the long run. Since I haven't actually built an engine in some time i honestly don't know what it cost to get there there with machine work and a set of dished pistons. Haha..

Originally Posted by bel_mor

My target static cr is 10.50:1

Choose a smaller target.... ~9.5:1 is about the limit for iron heads and pump gas these days, that's why I outlined a 9.6:1 build above. Choose a cam that closes the intake valve at about 35 degrees ABDC @0.050" tappet lift. If you are planning on using a flat tappet camshaft, please read through this tutorial several times....
http://www.crankshaftcoalition.com/w...ips_and_tricks

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