Originally Posted by Loudnproudford
Or .40 on head gasket I'm not sure yet
Have you ever used a compression calculator? They come in real handy when you start throwing all these potential combinations together. There's also a few Virtual Dynos on the 'net that will help you see how your different parts changes will affect your engine. They're very handy tools that'll save you money and frustration down the road. Of course, the dynos aren't 100%. Too many variables between theory and reality. But they'll get you in the ballpark of where you are trying to get with your project.
First thing you wanna do, is have a plan with where you're going with these mods, and what results are you wanting.. Also know that raising compression, just for the sake of it, is no good reason. Raising compression also raises the effective RPM range of your engine. If you want to keep your low end power, I wouldn't go much past 10.3:1. Most "torque" or truck cams don't like more than that. Unless you want your motor living in the 2800 RPM range and up, keep your compression ceiling in that area. Another thing to consider, once you get in the 10:1 compression range, you can pretty much kiss regular gas goodbye. It'll be 89 octane or bust from there on out.
Just my .02
'97 F-150 XLT Scab 4X4, 4.6L 2V
MSD coil packs, FRPP 9mm wires, Hi-flow cats.
IN PROCESS: PI swap w/ GT cams, Gotts Mod, Silencer Mod, 70mm TB