[maxrpm]

On the subject of power valve sizing, With your vacuum gauge visible while driving take the car on an open road to approx. 40-45mph and in your cruise gear(4th-whatever) accelerate up to 60mph as if you were increasing speed but not racing or trying to pass a vehicle. Note what was the lowest vacuum reading you registered. Now take that figure and -.5 that that would be your power valve size. So if you cruise with say 20in hg, accelerate and it drops to 7in. hg. Use a 6.5 p/v. You only want the power valve to open during heavy acceleration.