08Z51

Can someone tell me what the max safe static compression is on an LS3 with stock cam? I know I don't want more than 8.7 DCR but can't find stock cam abdc at 0.004 to calculate it.

Also stock ls3 is 10.7 SCR, but when I use the following in a calculator I get 10.9. What am I doing wrong?

bore 4.065
stroke 3.622
gasket 0.051
heads 68.5 cc (a few sources say 70 but numerous people claim to have measured at 68.5)
deck clearance 0.006 (entered as -0.006 since out of hole)
pistons 0 (stock pistons flat top)

thanks

KW Baraka

iTrader: (7)

First off.....you should EASILY be fine at 11:1 SCR with the stock cam with a tune and good quench. I'd go with .040" head gaskets.....

Also, did you calculate that SCR with 68.5cc combustion chambers or with 68.5cc chambers.

I ask because if GM says the LS3 is 10.7:1, and if GM says the chambers for the LS3 is 70cc, then maybe THEY calculated using the 70cc measurement.

Best of luck!!

KW

Dyno Junkie

I don't have a stock cam in our LS3, but I have had 0.075" machined of the heads and 0.100" flycuts in the pistons.

A.R. Shale Targa

iTrader: (2)

Pistons are .006" out at room temp
The deck of an alumnum block "grows"
Figure zero deck at operating temp and the GM numbers are correct