| Not a fan of power pulleys. There are few aspects of BMW that are poorly designed and engineered, but the cooling system is certainly one of them. Underdriving the water pump just doesn't seem like a great idea, nor does it seem bright to underdrive the alternator, the lifeblood of the car'selectronics. To me, this seems like something I would do way later on, or to a car I only tracked.
I would work on making the car work better. Continue to try and make the car more efficient without any downsides. Improving the CFM beyond a CAI (headers, M50 manifold, larger AFM, larger throttle body with ASC delete), or even hotter cams.
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