Aluminum Pullys

[mxz905]

Looking for opinions on aluminum pullys (Crank, alternator, etc) what sort of gains can one expect when swaping out to aluminum and is it really worth it. And do you need to swap all the pullys to aluminum or would you see gains from just swapping out the crank pully? Vehicle in question is a 05 GMC with a 5.3

[Jennabear]

You can get gains from pulleys but the metal has no type of impact.

[mxz905]

You can get gains from pulleys but the metal has no type of impact.

That said I assume gains can only be achieved by changing the size of pullys. I had been told that Aluminum pullys would produce gains do to their weight advantage. Less weight = less work on the engine. This sounds believable in theory however I always suspected that the gains would be so marginal they would be difficut to measure.

[Ape0r]

You can certainly show on paper that changing to (lighter) aluminum (or fiberglass?) pulleys will get you more power on the ground, but my professional opinion is that you'll never be able to tell the difference. Ever. Find some other way to lighten your wallet... like buying beer.

[nickvrebel]

the aluminum will also be a lot less durable - there is no gain worth having for that kind of a swap.

 

changing pulley sizes is a common mod, but it's a minor gain for $$$ invested.