Now I could be wrong here, so feel free to correct me if I am..A buddy of mine and myself are arguing back and forth on what the GMPP pulley sizes are for stage 2 and 3. I tell him that stg2 is 77.9mm(3.1) and the stg3 is 76mm(3.0) which is what I've read in a GM parts catalog online. He swears to me that stg2 is the 76mm(3.0) pulley and that stg3 is a 71.1mm(2.8) Who's right? Cuz he's driving me insane and refuses to believe me.

 

you are correct. 77.9mm = 3.06" = stage 2 and 76mm = 2.99" = stage 3

tell your buddy he's full of ****

 

my friend has GM stg2 with a 3" pulley

 

3.06 pulley

 

lol nice exactness sorry my eyes must be out of adjustment

 

are you seriously whoring both forums right now?....

 

It doesn't matter, I have an aftermarket 3.0" and get the 15 psi. those numbers from crate engine depot are confusing, yes...

 

Ok, second half of the argument...the stage 2 tune isn't good enough for that pulley, correct?

 

i don't think it is

 

none of the gm tunes are lol they are geared for being able to meet legality requirements in all 50 states AND to supposedly be safe as possible but

 

why ask the question when you know the answer.. and to the OP your right..

 

i have a gm stage II and it came with a 3.0 pulley and my tune is alright no black smoke like most other stock tunes

 

no it didnt come with a 3.0. it came with a 3.06.

 

He's still runnin the 42's too...most everyone i see on here with anything smaller than a 2.9 has the 60's, i assume they're required? Oh yea, he's claimin 300hp when he tells ppl about his car lol

For some reason he refuses the believe anything i tell him unless i also include that i brought it up on here and everyone agrees. He didn't believe me about cleaning his TB to fix his idling prob, then I told him i found it out on here and he believed me. He did it and no more idling prob...he no like to listen for some reason

 

looks like your buddy needs to take a step out of the toolbox if you get what i'm saying