Why do i hear about change the lower pulley, can you not change the upper pulley? and what is the equation for the two together? in other words how do you get say 12psi, or 14psi or16psi or any where in between? i guess what i am getting at is how to you figure out how much boost you have?

 

A 6lb lower will give you 6 more pounds of boost as with the same with 4 and 2, I don't really know how the upper works.

 

if you have change the upper and a #4 lower=#6 lower 0r 6 pounds of boost on top of your 8 pounds
if you have change the upper and a #6 lower=#8 lower 0r 8 pounds of boost on top of your 8 pounds
if you have change the upper and a # 8 lower=#10 lower 0r 10 pounds of boost on top of your 8 pounds