As the title says looking to figure out if I got the compression ratio right. I figured it to be 8.5 to 1. It is on a ls2 stroked to a 402. Stock Gm multi layer. Probably .60 thick.

 

if i figured it right on stock cubes/gaskets i got 7.6

 

Sorry it is a stroked ls2 so it is a 402.

 

depending on gasket its roughtly 8.5

 

I got 8.2.

 

Any one else? Different opinions.

 

Are the pistons at zero deck?

D.J.

 

with the calculator i use i came up with 8.64 with pistons out .008 thou and with a .055 gasket. the only exact way to get it is to cc the heads and pistons to verify they are exactly what cc they suppose to be and but you should be in the 8.5x-8.6x range.

 

I come up with 8.582 SCR using these figures:

Chamber: 70cc
Compressed gasket: .060
Gasket Bore: 4.000
Deck height: .008 above deck
Stroke: 4.000
Bore: 4.001
Piston volume: 28cc dish

 

8.58:1

4" bore x 4" stroke.
.051" compressed gasket thick with 4.030" bore
Zero deck
-28cc pistons
70 cc chambers