Mz3 SBC

Is this the standard pulley for LS GTO Alternator or and ASO overdrive?

I have a 25% reduction underdrive crank pulley - concerned about over revving the alternator since the car is a track car.

New to LS motors..so excuse the noob question!

i r teh noobz

iTrader: (4)

Not 100% sure without looking at mine, but that looks smaller than stock.

gMAG

iTrader: (1)

Looks like a standard/stock pulley to me.
What is the diameter of your alt pulley?
Also, what is the black thingie at the end of the alt pulley?

mantycarguy

That hub on the end of your pulley is an overunning clutch. The oems have been using these to save wear and tear on the belt drive systems and to suppress noise. With larger amperage outputs they needed these to keep the belt from fluctuating violently thus throwing the belt off during high load conditions.

Mz3 SBC

thanks....appreciate the replies. Thats a good thing I assume...since an overdrive might work the alternator too much at high RPM.

S10xGN

iTrader: (11)

Hate to break it to you, but an underdrive crank pulley drives all the accessories (including the alternator) at a lower speed than normal...