Anything else for Hp gains?

Jordo!

Ehhh technically nitrous induction is FI... and doing it right still means a tune that includes extra fueling, colder plugs, reduced timing potentially, etc.

Playing with different fuels and fuel mixtures requires tuning (and possibly different hardware!) too, but a bit more wiggle room in terms of margin for error.

Have any madmen on here played with nitromethane mixtures...?

FWIW, I have two comments on undampened pulleys.

1. So far, I have seen no confirmed evidence of engine failures due to one on a VQ37HR (I know of one "rumored" failure, where the pulley had seized to the crankshaft... bad install? Who knows?). Of course, I am not omniscient.

2. That said, the physics of undampened harmonics correspond to real world additional force exerted on reciprocating engine components. Accordingly, no car manufacturer builds a production motor with an undampened crank pulley that I am aware of. They build the engine with a dampened crank pulley with the specific aim of minimizing the extra stress caused by those harmonics, and the associated torsional and vertical vibration.

Individual results may vary, and some motors may be more susceptible to failure than others with prolonged stress from those forces, but I would say use an undampened crank pulley at your own risk...

EDIT: Oh -- duh -- just the alternator pulley? I guess that's okay if you don't have a powerful amp, but underdriving the alternator on a DD also sounds like a questionable idea, and power gains should be negligible relative to the (more inherently risky) crank pulley replacement.

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