... The efficiency of the 2.3 used the full benefit of that blower, while the KB unit was just getting into the efficiency range on the top of the rpm range. But that's the characteristics of big blower/little blower. ...
Wouldn't that be an argument for running a smaller pulley on the bigger blower, though? To put it into its efficiency range quicker? You can run a 2.8" pulley on the Whipple 2.9 on pump gas. For the '11/'12 GT500, you can run up to 21psi of boost on pump gas. I'm sure running a 2.8" pulley would nearly eliminate any advantage the smaller TVS has. I still stand behind my statement that a 2.4" - 2.6" pulley on the Whipple 2.9 would destroy a TVS running the same size pulley. Only problem with the Whipple there, though, is that you'd have to convert to E85 or race gas full time with a pulley that small.