Head choice, valve sizes and stages LQ9 heads
 

I am looking into some heads the larger chamber 317/LQ9 to lower compression a bit. Keep in mind this is for an LS1 stock bore. I want to run about 8/9lbs boost. What should I be looking for in regaurds to flow. And what about valve sizes intake and exhaust? Smaller valves or larger valves?

Should I stay with stock LQ9 valves or go larger?

http://www.exoticperformanceplus.com....html?item=409
These are the heads I recommend for your application. They are the same ones we used on this Corvette. http://www.exoticperformanceplus.com...Car.php?car=40 Bob

Whats the CR with those heads on a stock car?

From PM I recieved from Gunnar/patriot as I am considering the LQ9. I believe it was rule of thumb was 6 or 7cc per point of compression. I am not sure though.