alternator overdrive pulleys?

[96Blazer]

Ive heard of Underdrive pulleys. But never overdrive pulleys until i was surfing ebay just a little while ago. Would this be a good idea to get for my stock alternator until i get a HO alternator? will it up my amps at engine idle?

[Colin - STAPUFT]

Yes.

It will make your alt spin faster, getting the alt's output up to it's peak at lower engine RPMs. it also spins the piss out of your alt. They aren't magic and won't make your alt put out any more amps than it did before, it just does it now at a lower engine RPM because your alt is going faster.

I put one on a stock alt, then when I rebuilt my small case CS-130 GM alt I put it on there too. Yes it helped and it is much cheaper than buying a true High Output large case alternator, but as you implied- it isn't the best case scenario, especially compared to a proper HO alt.

I just wouldn't recommend blasting around town or going to the drag strip- OD pulleys put a lot more spin and stress on an already taxed alternator.

Hope this helps, bro.

[96Blazer]

yes. if i get one. id only have one on my stock alternator for two or three months at most. just until I could buy the HO alternator for my vehicle. so it looks like this is a good idea.