3" LS alternator underdrive pulley

I've been successfully running this inexpensive steel 3" alternator pulley to reduce alternator rpm longer than those companies have been CNCing logos in aluminium ones and charging 234% more.

This pulley diameter with a healthy alternator has the potential to maintain charging and battery voltage to nearly 7500 rpm where the stock pulley ratio can struggle as early as 6000.
Losing battery voltage causes a reduction in electric fuel pump volume and injector responsiveness. If there isn't enough room in the fuel pump volume and duty cycle to maintain fuel flow the engine will run lean and that's a wrap.
You wouldn't believe how many data logs I see to evaluate a converter that are loosing fuel pressure and Holley is taking the wheel on closed loop correction and duty cycle.