The Blower Thread

Need some Pulley help here guys - my current set up with 6.75 / 3.12 is making 15lbs of boost. I need to bring that down to 10-12...would a 3.33 do it or a 3.47?

It’s a Vortech v2 with a 4” Powerpipe
3.33 should do it . Sounds like something is a restriction - what’s the heads and intake combo ?
 
Another blower pulley question here. My V3 kit is the basic entry level kit advertised at 5-6 psi. What diameter 6 rib pulley comes on this kit?

I ask because I already upgraded to a 6.87 crank pulley with 8 rib (but running 6 rib belt) makes 8-10 psi. I might want to change the blower pulley to 8 rib and go down in diameter for some extra psi. I guess Ill need a wider idler pulley too, and obviously an 8 rib belt.
 
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I bought an 8 rib 2.95" blower pulley, 8 rib idler and 8 rib belt. My current crank pulley is 8 rib 6.87". Vortech calculator says blower impeller will be at 50k at 6000 rpm. With my current 3.33" blower pulley I get 8-10 psi depending on how cool the weather is. We'll see what happens.

Anyone have any cautions for me on this experiment?
 
I have a V1 but how do you know what compressor you have? or Trim?
 
I have enjoyed reading the post's very good information, I do have a question, I have a vortec v3 si to install on my 90 gt, unknown miles, I did a compression check it's at 150 to 160 psi. on all cylinders, will that be ok or do I need to freshen up ? if I have to freshen up what type of rings (material) do I need to install ?