my brother-in-law owns an 01 Sierra and got some smaller pulley's a while back. he barely added the alternator pulley a week ago but notices that the volts drop when he is idleing.

My question was about the alternator. should he leave smaller one on or should he go back to stock? which would be better? i also thought i read something about an overdrive pulley, is that just a bigger one than stock and does it work better?

thanx

<small>[ January 31, 2003, 03:32 AM: Message edited by: speeder_08 ]</small>

 

I have a set for mine that I'm going to be installing on my 01 sierra. I didn't size the alt pulley to the stock one but I'm supposed to have the alt pulley that maintains that compensates for the decreased charging level. I'll post my findings when I get back to the house and get them on.
Lar

 

Drive Pulley = Crankshaft Pulley. Driven Pulley = A/C pulley, P.S. pump pulley, Alt. pulley, Water Pump pulley. Drive pulley: smaller dia. = underdrive, larger dia. = overdrive. You want your crank pulley to spin the parasitic devices that load it down(rob power) SLOWER. You alt is OVERDRIVEN at all speeds above 2k so the only thing your doing above that speed is prematurely wearing out the bearings not making more current. It only underdrives at idle speed which most driving isn't done at idle speed hopefully.