[6speeder]

Here is a graph comparing stock heads to ported and decked (.03", to give 11.8:1 CR) heads by Texas Speed.

All mods on car before and after: QM600 cam, American Racing Headers, ported intake manifold and throttle body, 160 thermostat and a tune. So the ported and decked heads gave me 25 rwhp and about 28 ft-lbs of torque. Runs on the same dyno, A/F very close, a little richer with the decked heads (12.6 Vs 12.8) This is a somewhat conservative dyno, stock Z06's get 440 to 448 rwhp.

 

[Barricade]

An extra 20 wheel ain't bad lol.

 

[SLOBRA]

From just heads? Is that good? Sounds good to me.

 

[1evilgoat]

not bad at all

 

[TRMIN8R]

That is very good, to get that much more power out of an LS7 is impressive.

 

[6speeder]

The LS7 heads are VERY good stock. They are already CNC machined from GM so major gains just aren't possible. The graph shows they flow well without losing port velocity, so the gains are EVERYWHERE, not just at high rpm's. Done this way, I gained 30 ft lbs of midrange torque, better throttle response, and my gas mileage is up a bit. Also, the heads are more efficient, they don't want lots of timing, anything past 24 degrees showed no gain in power.

 

[zinister]

Right on!

 

[Yahtzee]

dang sick torque curve!!

 

[pullinboost]

nice #'s!!!!