On a p-1 a 4.0 pulley is supposed to make 8-9 psi? So around what size would I need to make 13-14 psi?

 

the first question would be ARE YOU MAKING 8 -9 with the 4.0" pulley...then go from there...it is dependent on your specific set-up...I made more than that w/ a 4.0"...the smaller the pulley you go with the more you will have to look at remedies for belt slip as well...

 

8 psi is what it's making. It is a 6 rib system so I'm sure belt slip plays a major role.

 

If you haven't already done so, you should look at repositioning your idlers for more belt wrap on the ProCharger pulley. I also think that I eliminated alot of belt slip and/or shock by going with a MUCH larger tensioner pulley. I attempted to go from a 4.0" to a 3.4" and grenaded my high mileage P1SC a couple of years ago.

 

what are your cam specs?what rpm do you shift at?

 

220/220 .581/.581 112 may not be the best for boost but when I ran across the charger I couldn't really pass it up cuz of the deal I got. Shifts at 61-6200