Chevy High Performance 350- Fit or no fit?

[MikeB]

Originally Posted by Jake Wade

More like 7.8-7.9:1. One would be better off with the 260HP version with that paltry CR.

I agree 100%. Cylinder pressure with the bigger cam is very low. And that means low torque and not-so-great throttle response, certainly under 2500 RPM.

I don't know what GMPP was thinking, unless they wanted a lopey idle (misfires) and didn't care about loss of torque. At least they could have selected a cam with a tighter LSA, or cylinder heads with smaller combustion chambers. I think CompCam's #12-306-4 at 206/212 on a 108 LSA would work much better than the larger GM cam. You can also get it on a 110 LSA as #12-308-4.

On another note, I have had a couple 9.0:1 to 9.3:1 engines with iron heads, Neither one needed premium gas except on very hot days with coolant temp at 200-210. Of course, quench height on both was in the .040"-.045" range. On the GM crate engines it's .060"-.070", which is more prone to detonation.