Compression and combustion chamber volume

Discussion in 'Technical' started by BLACKANGUS, Dec 14, 2004.

1. #1
Currently I'm running a 58cc L98 vette head on my 350. The pistons have 2 valve reliefs, 5cc in volume. Deck clearance is .025" I figured compression would be in the 10.5:1 range. I found some really nice Kenny Duttweiler Trick flow heads with a 64cc chamber, does anyone know a compression ratio formula, or without doing the math is there any way I can guesstimate, doesn't need to be exact but I want something above stock compression which is 9.3:1. Thanks

2. #2
Compression ratio = cylinder volume at BDC / cylinder volume at TDC

so....

CR = Displacement + cylinder volume at TDC / cylinder volume at TDC

CR = (Displacement / cylinder volume at TDC) + 1

3. #3
a composite one for iron to aluminum is .051 compressed, I used that for calcs

original compression was exactly 10:1 with stats provided
new compression with 64cc chamber would be 9.37:1

if original compression was 10.5:1
new compression would be 9.8:1