And find the restriction
Ok so I'll send it to you.

I can have it on a truck next week!!!
[emoji24]
I know the truth... All you do is workout and talk on the phone. Lol

F1a is 5:10 and the F1r is 5.40.That's a little more like it in regards to boost. What sort of power are you making?
How do you calculate the step up RPM on the PC?
When does the boost really start to come on with that blower?F1a is 5:10 and the F1r is 5.40.
The crank pulley 7.5.
My 3.9 used to make 24 psi with my 3.9 on an F1a with ported heads. It now makes 21 psi with the gutted heads.
When does the boost really start to come on with that blower?

Your right, I don't know what I was thinking.F1A is 5.40 just like the F1R
https://www.procharger.com/superchargers-automotive?qt-supercharger_models=0