At mild boost levels, the "efficiency" of the various latest edition belt driven blowers varies very little. The hybrid Roots blowers are pretty good. The stock Whipple is a bigger blower than the Maggie pumping more air. It's not hard to figure out why, when comparing stock vs stock blowers, that the Whipple makes more power. Compare them both at say 9ish psi. There won't be much difference. On an LS3 sized motor, the smaller blower will actually be stronger down low and give up very little on the top end. The 2.3L blower is an excellent match for a 6.2L motor. As you push things harder and the boost goes higher, the bigger blower will eventually have advantages. You probably won't find them on a stock motor.....at least not for very long
