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Old 04-10-2009, 02:47 PM   #30 (permalink)
semtex
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Quote:
Originally Posted by Bster View Post
Erm.... Sorry for sounding noob, but what is this UD pulley used for and what kind performance gains are we to expect?
I was about to explain it, then I realized that you can just Google it and get your answer. In a nutshell, your auxiliary items (like the air conditioner, for example) are powered by a crank pulley. An underdrive pulley is smaller and lighter, and sends less power to those auxiliary systems because they don't actually need as much power as the stock pulley generates. Power that is sent to those systems is power that is taken away from your wheels. So by replacing the stock pulley with an underdrive one, you are returning some of that power back to the wheels. End result = gain in whp.

Here, go to this link, it explains it more fully and better than I can: Underdrive pulleys - Wikipedia, the free encyclopedia



Edit: Here is the link to Stillen's web page for the pulleys.

http://www.stillen.com/product.asp?i...SAN&model=370Z
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Last edited by semtex; 04-10-2009 at 02:51 PM.
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