Carb power valve plug

correctly compensate for the PVRC...power valve restriction channel is to calculate the area of the channel...and calculate the area of the jet you have...add the two areas together...and then fine a jet is equal to that area....

or as most people do...add 8 or 10 jets richers...

the only thing a power valve does for a drag car is ...keeps mixture lean (and clean) while pudding around the pits at part throttle...

but i use them..in the front..