Originally Posted by bygddy
Your confusing drivability, or perceived responsivness...with HP, the issue isn't really which makes more power, the 750 wins, almost everytime,people say all you "need" is a 570, or a 650 etc, based on a formula that Vinnie is referring to above. And its accurate, but flow is flow......if your building a performance motor, you want flow, and in this instance, for sheer numbers, bigger is better....on the dyno, the 750 will outperforme the little 570 every time......
only way that is true is if you are looking at peak hp
you also left out other facts.. like factory heads flow compaired to aftermarket...
ya a 350 with heads designed to make peak power at 6500+rpm.. ya you'll need a 750
if he drives like most the 350 will be used 95% of the time from idle to 4000-4500, a 750 d/p is giving away torque.. and lots of it..
now a 750 vac 2nd thats different .
iirc a 350 would have to be 95% Volumetric Efficiency @ red line
redline being (in this exp 6500) to need a 750 cfm carb..
most mild builds that are not pro built are under 85% vol. efficience..
you'll find bottlenecks else where before the 650 carb becomes one..