GMPP/EDDY HEADS

[Vince]

Hi fellas.

I have basically new GMPP heads from a ZZ502 heads, 290cc intake, 110 chambers, 2.25/1.88. I think these flow about 300 cfm at .600, and not much after that. Question is, what kind of real world HP can one expect after getting some port work done, and not loose any low-end? Does it pay just to get another set of heads? This is on a 454, 9.7:1, 231/239 .6/.6 HR.

Also, these "roval" ports are unique and the only intake that seems to fit well IMO is the stock GMPP intake, which has been cnc port matched, it looks like a dead ringer for an RPM intake. Any gains massaging this also?

Thanks Vince

[Mike Stark]

You could see as much as 70 to 75 HP gain from porting alone. That would be a full port and polish. I have several guys running these heads making really good power. The intake would see some slight gains with work, but not much.

[Vince]

Thanks Mike, what "stage" porting would this be. And, I guess the intake is worth keeping providing it doesnt need a whole lotta work?

[Mike Stark]

That's a Stage 5 full port. Keep the intake for what you are doing.