9:1.
Wiki User
∙ 13y ago8.5 to 1 compression is factory stock.
8.3:1 is stock
6 to 8 degrees advanced. for stock compression ratio.
305 Small Block Chevy engines typically were 8.6 compression ratio and would use 87 octane fuel.
The stock compression ratio for a 2003 Yamaha YZ85 is approximately 8.6:1.
10.5-1
Yes, they will fit on the block. The larger combustion chambers of the 307 heads will probably reduce the compression ratio by a fair amount, reducing power output.
It varies from 145 to 370, depending on a lot of variables including compression ratio, cam profile, and head design.
The stock compression ratio for a Suzuki QUV 620 is 10:3:1. Special spark plugs can increase that compression and the horsepower.
11.3-1 stock piston with stock 3 layer base gasket
It is 8.54 ~ 10.12 :1
Compression ratio on a 1974 Chevy 350 in a Nova was 8.5:1.