I've always tuned the surging out of the roots blown motors I've built and tune, carbureted, mechanical injection and EFI wrench scope
Make them idle around 1000 to 1200 RPM in neutral and close to 800 to 1000 RPM in gear.
This video looks like you change the blower, is that a 10:71 or a 12:17? confused

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)