Compression ratio question
Thread Starter
1st Gear
Joined: Jan 2007
Posts: 1
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Compression ratio question
i got an old 327 i think, havent took apart yet. did look up head casting numbers on internet say they are these................................
3890462....66-67...302/327/350..Camel hump,no accessory holes,64cc chamber.
ok my question is with 64 cc chambers and engine with flat top pistons what compression ratio will this be?
... and also what are the chances these heads have the 2.02 valves?
3890462....66-67...302/327/350..Camel hump,no accessory holes,64cc chamber.
ok my question is with 64 cc chambers and engine with flat top pistons what compression ratio will this be?
... and also what are the chances these heads have the 2.02 valves?
Racer
Joined: May 2006
Posts: 293
Likes: 0
Are there any valve relief notches in the pistons? If so what are the ccs? What is your deck height? How thick is your head gasket and what is it's bore? With answers to those questions, you will be able to figure your compression ratio.
Advanced
Joined: Aug 2006
Posts: 65
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For a std. bore 327 and 64cc chambers, my math shows 9.2:1 with 5cc valve reliefs, .038" gasket, and the piston .025" down the hole.
With the same pistons, .028" gasket, and "zero" deck, it's around 10.0:1.
Each cc of volume changes the compression ratio by approximately .11.
With the same pistons, .028" gasket, and "zero" deck, it's around 10.0:1.
Each cc of volume changes the compression ratio by approximately .11.
