Compression ration assistance, please?
Compression ration assistance, please? I have a 6.0L iron block, bored to .030 with a 4" crankshaft and 6.125 rods, the pistons is a -29 cc one (JE). My questions is: what's the CR if I use the mentioned combination with a 243's head with 64cc chamber and if I use a 317's with 72cc chambers? I'm planning to go twin turbo. Also can use a standard stroke crank with the 6.125 rods and flat pistons (Diamobs-3cc's); by using the same heads, what would be the CR and which combination would be better for the TT combo?
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Joined: Nov 2003
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From: Norn Iron
I'm only looking for an estimate. I don't know about numbers, just what I wrote at the beginning of the post; no idea of gaskets gross/thickness or other number to calculate. Can you do some numbers???
If YOU don't know what you are using to build the motor, how can anyone else give useful info?
With those je pistons and using ls9 gasket with a compressed thicknss of .051 and assuming the pistion will be .007 out of the hole. If you have stock deck 243 heads your compression ratio will be ~8.9:1. if you mill the heads .006" for every 1cc of volume and you mill them down to say 61cc your compression ratio will be ~9.1:1
