15 psi on a blower? That's a lot.. Hope your motor is built for it.

I talked to Adkins Rotary today (they bought Camden) - they said that their blowers were rated to produce X max boost at peak rpm.. So I am seeing what is advertised for my blower, 4-5 psi at 4000-4500 rpm, WOT.

Cruising around, 2250 rpm, I can see 2 psi or so.. Not very much, I'm going to upgrade to an 8psi peak pulley. That should give me 4 psi under normal acceleration conditions.

My gas mileage is CRAPPY - anywhere from 10-14 mpg. I like the motor, it makes neat blower noises, but a 4.3 is a much better swap for a lot of reasons!

-d