If i install an ASP crank pulley, will it lower my volatage level at idle? I currently at some times run at 550 rpms the monsoon stereo, 100 watt amp, sub, bottle warmer, radar detector, A/F gauge, and the AC. I couldn't afford to lose any voltage.

 

I didn't see any loss untill I turn on my head lights, fog lights, ac full blast and my rear defroster. But then again I have an M6 and it idles higher than an A4 in gear. My old 96 Z A4 with a crank pulley had noticably lost alternator charging at idle with just head lights and ac. The voltage guage needle was touching the lower red zone. Hope this helps!!!