View Full Version : power valve

04-22-2007, 01:31 PM
what size power valve should I be using on a 750 demon with 10" manifold vacuum?

04-22-2007, 06:45 PM
See how much vac you have in gear with your foot on the brake.

Your PV should be 1.5" to 2." lower than what you have in gear

05-01-2007, 10:17 PM
Yeah for the most part I have been using anywhere from 3.5 to 5.0 and so far the 4.0/4.5 are best for street with moderate cams(I have an LT4 HOT roller).