Hi Danny.
This brings up images of the supercharged cop car in Mad Max!
With a centrifigal blower, and the speeds they turn, I'm not sure how long a blower would last if you banged it into "gear" at say 5000 rpm.
In my case with my last blower I used a 6" crank pulley, and a 2.25 blower pulley, and the internal drive was 3.33 to one...(as I remember)
So at 5000 rpm my 6.2" impeller was spinning at 44,439.998 rpm.
The new one I have coming has a 4.1 to one internal drive, and a
6.9" impeller!
I have been getting 18 mpg city and 21 highway, and have been very happy with that.
A roots type blower has alot more internal mass to start spinning, not to mention the resistance of compressing the air.
With mine, at 3000 rpm cruising, (72 mph w/4.44s) If I have light throttle its only 2.7 or so psi.
So untill you drop the hammer it drives like a normal car.