Here are some numbers for a static compression & leakdown test on my 340 T/A engine. Cylinders are bored .030 over, I don't remember the head milling, but I'm supposed to have a compression ration of 10.2:1. The cam is a Comp Cams Hi Energy 268 (218° @.050 / .464"). The engine has 40,000 miles on it's rebuild.

Compression-static
1) 141psi 2) 140psi
3) 145psi 4) 140psi
5) 140psi 6) 142psi
7) 140psi 8) 141psi

Leak Down Test
1) 6% 2) 5%
3) 5% 4) 3%
5) 2% 6) 4%
7) 5% 8) 5%

Thanks!