Underdrive Pulleys Install
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From: Albany
Underdrive Pulleys Install
I am thinking of installing a set of underdrive pulleys on my '03 S. Has anyone done this and what type of performance gains have they seen? Also, where is the best place to source them out?
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From: Sydney
Ricks made some for a while but no longer do (if I remember correctly).
I'd recommend a search before going any further with this. From what I remember the advantages were nil, the cost sky-high, and the risk of damage not inconsiderable.
I'd recommend a search before going any further with this. From what I remember the advantages were nil, the cost sky-high, and the risk of damage not inconsiderable.
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The pulleys that have been available for the S2K were NOT underdrives. They were just light weight pulleys in the OEM sizes.
There will be less benefit from underdrive pulleys since the power steering is electronic. The only accessories that can be underdriven would be the water pump, A/C compressor, and alternator. Considering the A/C compressor is probably going to be off while driving aggressively, and the alternator load is more dependant on the electrical load than it is the speed of the pulley ... the water pump is the only real power saving portion. Considering the water pump may use about 10 HP, then underdriving it by 20% would only gain you 2 HP. You would also have side effects (some good and some bad) from underdriving the water pump by that much. Coolant flow at idle would probably be too low to maintain normal temps, but coolant flow at redline might be improved.
Before you consider sourcing custom pulleys, you should investigate an electic water pump. That would give much better gains with less side effects. It would probably even be cheaper.
There will be less benefit from underdrive pulleys since the power steering is electronic. The only accessories that can be underdriven would be the water pump, A/C compressor, and alternator. Considering the A/C compressor is probably going to be off while driving aggressively, and the alternator load is more dependant on the electrical load than it is the speed of the pulley ... the water pump is the only real power saving portion. Considering the water pump may use about 10 HP, then underdriving it by 20% would only gain you 2 HP. You would also have side effects (some good and some bad) from underdriving the water pump by that much. Coolant flow at idle would probably be too low to maintain normal temps, but coolant flow at redline might be improved.
Before you consider sourcing custom pulleys, you should investigate an electic water pump. That would give much better gains with less side effects. It would probably even be cheaper.
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From: South of the pier, Huntington Beach, CA
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From: Kinda Close to St. Louis
[QUOTE]Originally posted by Sideways
Check out: http://www.proautosportsinc.com/home.htm
Save over 5 lbs on the crank pulley.
Check out: http://www.proautosportsinc.com/home.htm
Save over 5 lbs on the crank pulley.