to underdrive or not to underdrive....

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Nov 22, 2005 | 07:51 PM

gnar-de-gwar

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to underdrive or not to underdrive....

should i go with an underdriven pulley (UR) or lightened (ZPI, or Agency Power)

Nov 22, 2005 | 08:38 PM

RTon20s

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I think the answer is obvious. The power difference between the two will be negligible. However the loss of efficiency in your accessories is a negative only attributed to the under driven pulley.

Go with the lightened stock diameter pulley. And if I remember correctly, the Agency Power is the cheapest through Vivid Racing.

Nov 23, 2005 | 05:37 AM

edxa

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Go with the lightened pulley.

Nov 23, 2005 | 07:54 AM

gnar-de-gwar

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lightened it is! thanks guys...unless anybody has an objecting opinion?

Nov 23, 2005 | 08:35 AM

killerxromances

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Quote:

Originally Posted by gnar-de-gwar

lightened it is! thanks guys...unless anybody has an objecting opinion?

Good call, go with ZPI's pulley. 1.1lbs, lightest pulley out there right now!

Good luck!
Cya

Nov 23, 2005 | 04:34 PM

RTon20s

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Do we know for a fact that the ZPI is the lightest out right now? I have never seen the actual weight for the Agency Power.

Not to mention the fact that there is speculation that the ZPI pulley is a repackaged Agency Power pulley. And if that is the case, the Agency Power can be had for less through Vivid Racing.

Nov 23, 2005 | 10:40 PM

Rocket

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I have the Unorthodox and I am very happy with it. I used the stock belt and could feel the power increase. Just my 2 cents!

Nov 23, 2005 | 11:19 PM

TheScionicMan

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I agree with RTon20s, I can't imagine there is enough difference to justify the potential negatives.

As for the lightest, you're talking about 1.1 vs. 1.3 lbs on the Perrin, I believe. You're still shaving off 4... At that point it's probably not even a measurable difference in effect.

I'm gonna take the washers off of my bolts to lighten it up even more... hehehe

Nov 24, 2005 | 05:57 AM

hPower

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ok, here is some info regarding pulleys.....

Less weight = more throttle responce.

Underdrive = more power sent to the wheels and less sent to accessories.

So theoretically an underdrive pulley will show more HP when set up on a dyno. If you are going for the BEST bang for the buck you should go for an underdrive pulley.

If you want the best of both worlds you should look up NST, www.NonStopTuning.com
They have an Underdrive crank pulley AS WELL AS an overdrive Alternator pulley. You get the extra HP and your main accessory (the alternator) does not suffer as a result!

NST rocks