i looked in the Moroso catalog and they have the underdrive crankshaft pulleys along with the water pump and other ones. With the crankshaft pulley it shows a 30% and 50% underdriven ratio. which one is better to use? i know there must be a differenece but which one will be the best to go with?

 

Is there some reaon you need to reduce the speeds of your accessories? Does the Moroso information include a dyno sheet demonstrating any change in engine performance with eother swet of sheaves? I'd want to see that before installing any different diameter sheaves.

Try the SEARCH function. You'll see a lot threads regarding the typical problems generated as a result of installing underdrive sheaves, and precious few showing any actually measured improvements.

 

underdrive pulleys are just another form of snake oil.i myself have a set of March underdirve pulleys and i saw no change in preformance.if you buy a set don't expect nothing more than a little more "Bling" under the hood

 

Have the March underdrive crank and pump pulleys on mine. No real problems but I doubt there's any real power increase either that I can feel. Look real nice.

 

What is eother,swet, and sheaves?

 

That's called a White Russian with a ScrewDriver having Sex on the Beach.

 

i know i don't have any slips to back up my claims, but i have a few buddies who have gained a tenth to 2 1/2 tenths with just pulleys. most everyone has claimed an increase in fuel mileage too, which is the biggest reason i want to get some...

 

That sounds about right

 

Where do I sign up for this?