Vortech has an impeller speed calculator that has the 3.6 step up ratio and allows you to vary pulley and engine rpm.
The first listing on their calculator is for use with jack shafts. This allows a variable to be entered converting to a new answer. http://www.vortechsuperchargers.com/...d%20Calculator

By entering the Vortech ratio 3.6 at the first jack shaft cog pulley teeth and the Novi ratio 3.45 as the second jack shaft cog pulley teeth it should give you proper results.

5.45 inch crank pulley
9000 rpm
3.6
3.45
3.2 inch pulley

53029 rpm impeller speed.

Anyone want to confirm this works out correctly?

 

With my formula its a little off from what you have. My spreadsheet does the math for me.

3.45in Step up
5.45in Crank
3.20in blower
52,882 @ 9,000 RPM