I need to know what blower pulley I need to make 7-8psi on my setup.

P1SC1 with 8 rib kit twin 3.5inch intercoolers
Ms3 size cam 6500RPM shift points
Hooker Supercomp headers 1 3/4
Corsa catback
Fast 90/90
Stock Heads 853 casting
Approx 1117 feet elevation

Currently I am going to run a 3.85 blower pulley, I dont want this to be too much boost. I am on the stock shortblock. Hopefully I wont have to find a different belt size this one was trial and error for me and took a lot of time.

 

i could be wrong but i think a 4.5 i what came on my d1 for a stock short block, and the 3.7 is what was suggested by ati for 12-14 lbs on my new 402

 

I think a D1 will make more boost than a P1 with the same pulley. Nobody has a similar setup?

 

Must be a secret and I dont know the special password.

 

Correct. But more importantly, a D1 will make the same amount of boost with a larger pulley. The larger pulley on the D1 will allow the S/C to spin at a lower rate to make the same amount of boost. Since the S/C is not spinning as faster, the intake charge will have less heat in it and that is a good thing.