[mustangs4life]

Hey guys, are Uderdrive Pulleys worth the money? The American muscle ones say they add 15 HP, but i have heard of them frying the alternator and stuff. So I was wondering if anyone has them or knows anything about them. And do they really bring 15 HP or are the numbers just an exaggeration?

Any comments are helpful, thanks. Here's a link BBK Aluminum 3.8L Underdrive Crankshaft Pulley Kit (94-98 V6) at AmericanMuscle.com - Free Shipping!

Also that says Underdrive Crankshaft Pulley kit, is that the same thing or different? I really dont know much about this, so as i said before any info is appreciated.

[goren813]

They don't add HP, they simply "free up" existing power by running less of it to the accessories. I haven't of them frying alternators, only thing is if you run aftermarket electronics, I'm talking big systems, you'll want the alternator overdrive pulley as well. With stock or near stock electronics and accessories you shouldn't have any issues.

...probably isn't going to give you 15hp, but you'll feel a difference in butt dyno. From what I hear and have seen they are a good mod.

[Codeman]

I think that they are worth the money. I would definately try to find a used set. In my opinion on bolt ons I would say 1 would be a tie between windstar and gears. And number two would be UDPs. By far the top three mods. All other bolt ons such as exhaust cai basically add little power, mainly sound and crisper response.

A comparison would be like driving with your ac on compared to with the ac off that is about the difference that udps make. They have reported around 7 plus rwhp gains on them.