i was looking at the zzp 2.85 or the 2.7 pully for my car but i would like to how much boost i would see with each of these pullies? also if i buy the gm stage two replacement belt would it work on ether of these pullies or would i have to get an adjustable tensioner?

 

i have the zzp 2.85 runnin with the stage 2 belt, no slip, the 2.7 from what i hear the belt should be ok too.

 

I'm running the Billetflow 2.7" with 42lb injectors. I'm seeing 17.5psi with the car all stock. Once I get the K&N intake I have put on and then port the throttle body and blower I'm expectiong 19-20psi. I'm very happy with my pulley size - don't go smaller than a 2.7 IMO...

 

did you need the idler or you put it on just incase the belt slipped?
also did you have to shave the braket the idler pulley fits on?