What gears produce what psi of boost?

[Apex Man]

I'm getting an MPI 10 psi SC kit for my Apex. What drive and driven pulleys will that come with? What ratio do I need to get only 7 psi? Gear ratio for psi calculation doesn't seem to be linear. I will spin 10,500 max. I really only need 7 psi but I'm getting a good deal on a 10 psi kit. Just need to know what I have to change for various boost levels. I can get the taper-lock pulleys locally and I'd like to get everything I need to make the change.

Thanks,
Ralph

 

[Bossman]

If you are getting the kit with pulley set to make 10 psi those pulleys you are getting can be reversed from top to bottom to make 7 psi.