always had one cyl down on compression that i suspected was the issue. went looking for this sudden increase in acceleration induced blue smoke and i found another cyl on the same bank that seems to have lost 40 psi since the last time i checked compression. this rebuild doesn't have 5000 miles on it. but a lot of it is running @ the drag strip. just got a lot worse @ the first drag race of the summer last week. ( summer just starting here in Canada). the first thing that comes to mind is a broken ring, or head gasket failure. My question , is how to methodically diagnose this prior to disassembly. 410 mag block, w/ edelbrock heads, atomic injection, keith black hypereutectic pistons 40 over. rev limiter set @ 6100rpm.