Whats the difference?

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Nov 2, 2005 | 07:37 PM

KendallRS

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Whats the difference?

Whats the difference between an Under drive pully and a lightened pully?
And i have heard that an underdrive pully will eventuall snap the belt tensioner bolt, will this happen with a lightened pully as well? And what is the signifigance of an underdrive and light weight pully?
p.s. 2000 rs

Nov 2, 2005 | 07:48 PM

VRT MBasile

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heres what it is to the best of my knowledge:

undedrive: changes the ratio of power to certain pulleys, but is overall harder on the engine components?

lightened: a lightened pully is just that...a pulley that is lighter, but same amount of power is given to everything (a/c compressor and whatnot)

EDIT: a lightened pulley will not harm the engine. anyone may feel free to correct me if I'm wrong

Nov 2, 2005 | 07:53 PM

KendallRS

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But will the lightened pully do anything for performance?

Nov 2, 2005 | 07:54 PM

VRT MBasile

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yes, because the crankshaft has less inirtia to oevercome due to less weight.

Nov 2, 2005 | 07:57 PM

KendallRS

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thanks

Nov 4, 2005 | 12:43 PM

AWDimprezaL

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Quote:

Originally Posted by MBasile

an underdriven pulley would make the accessories last longer because everything is turning slower then it would be, no harm will come of this, unless you have a large stereo, then the alt wont be able to keep up. Lightend and underdriven pulleys wont hurt anything

Nov 4, 2005 | 12:49 PM

VRT MBasile

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Quote:

Originally Posted by Unorthodox Racing Website

However, we do not push the amount of underdrive for two main reasons. First, it is important to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving.

Just some info I dug up