Guys I'm confused how do you measure comptech pulleys, just the outside diameter?

Also according to this if i get a 4.0" I'll get 8psi (or 7.5 with ac) on my ap1?

I must be running the 4.25 on my AP1 as is standard for Ap2, Im sure im running near 7psi.


For Comptech:
4060400 Standard AP1
4060395 4.25inch
4060390 4.0inch(7#)
4060385 3.5 3.35inch
4060380 3.25inch
4060370 3.0 inch

thanks

 

Bump