i have a powerdyne sc with the 6psi pulley, and i want to increase the boost. do i have to use powerdyne pulley's or is there another type of pulley i can use if i dont like their selection? i think i would like to go to 8 or 9psi, do you know who makes these? thanks

 

go to e bay, look in the auto parts section, under super chargers type powerdyne,
928 should have some pulleys up for sale.
the one your looking for is the 2.70 and yes you will need to get it machined so it will fit right on the unit, if not you will toss the belt for being to far out.
you will need a shorter belt, the belt for the 2.93 is too long for the 2.70 I went with a
dayco 5060923 by pass the idler pulley next to the alienator, should be a good fit.