I've tried a larger pulley. I loose voltage at idle or at a traffic stop. The more things online, the more the demand on the alternator. I have a double crank pulley. The second groove is for the A/C. This alternator was originally made for a serpentine belt but can be purchased with a v belt. It puts out 80 amps at idle and 120 amps peak with very little voltage drop. Heavy rain it will slip and drop voltage to 12 volts. I switched the belt from a 7360 to 9370 belt. That number is the same from Napa or Gates. That helped but so would a splash guard.