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does a underdrive pulley work

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Old Nov 22, 2007 | 02:44 PM
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Default does a underdrive pulley work

im planningm on buying a underdrive pulley and i wanted to know if its worth the money???
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Old Nov 22, 2007 | 03:20 PM
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It depends. How much are you willing to spend on 6-8 rwhp? If 6-8 rwhp isn't worth $170 to you...then no. It's not worth it.

However 95% of the people on here, think it is.
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Old Nov 22, 2007 | 03:35 PM
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then im for it
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Old Nov 22, 2007 | 03:35 PM
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Yes, I thought it was definitely worth it....besides the small hp gain, the engine revved noticeably faster.
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Old Nov 22, 2007 | 06:31 PM
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Originally Posted by Grimes
Yes, I thought it was definitely worth it....besides the small hp gain, the engine revved noticeably faster.

Ditto!
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Old Nov 22, 2007 | 06:43 PM
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What's the drawback then, other than the cost? Will this hurt you if you run big subwoofer amps?
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Old Nov 22, 2007 | 08:29 PM
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Don't - dead battery and the performance gain is minimal; less than what people want to think.

Do a search on more than just this forum. I did and decided no. I think people believe in it but unless you're into pure track performance, I wouldn't bother. Take your spare tire out, run with a half tank of gas and gain more acceleration than the UD pulleys can provide. Your electrical / cooling system will thank you. Just another opinion though....
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Old Nov 22, 2007 | 09:24 PM
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i have had no problems out of my asp. works great.
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Old Nov 22, 2007 | 10:39 PM
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Originally Posted by 01Z28M6
Don't - dead battery and the performance gain is minimal..... I ... decided no. Just another opinion though....
Even though my voltage gauge reads 14.1 both with stock and U/D pulley (don't forget about the voltage regulator in the alternator)? At 8 hp for $175 that is $22 per hp. A do-it-yourself cam install costs $750 for 40 hp for $19 per hp. The deciding factor should simply be if you want to spend the money or not.
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Old Nov 22, 2007 | 10:48 PM
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Although I didnt dyno after adding just the pulley I felt absolutley no diference.
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Old Nov 23, 2007 | 01:18 AM
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its worth it, but there are other mods ie headers that you should do before you do this one
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Old Nov 23, 2007 | 01:34 AM
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Originally Posted by Tainted
its worth it, but there are other mods ie headers that you should do before you do this one
x2 save up and get yourself some pacesetters or somethin
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Old Nov 23, 2007 | 07:14 AM
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Its def worth it, will maike 8-10 hp. No loss of driveability.

I dont run a large stereo system, my bud's 02 z28 charges fine. I would do the pulley when your doing a cam, its a PITA to take out and put on but its free hp and free labor if doing the cam.

I will be getting a SLP UD pulley.
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Old Nov 23, 2007 | 08:24 AM
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Originally Posted by Chevy406
Even though my voltage gauge reads 14.1 both with stock and U/D pulley (don't forget about the voltage regulator in the alternator)? At 8 hp for $175 that is $22 per hp. A do-it-yourself cam install costs $750 for 40 hp for $19 per hp. The deciding factor should simply be if you want to spend the money or not.
You are correct as the voltage regulator does factor into it. The down side of that is the alternator is commanded at full load much more now. When a battery is very low, you should put a charger on it rather than allow the alternator do the heavy charging for an extended period. Essentially with an underdrive set up, the regulator is commanding the alternator to work under a heavy load more often. So my decision to fore go the pulley mod had to do with the component life of the charging system as well. I notice how the defense for using the pulley keeps upping the horsepower. On the low estimate is 2-5 horsepower and some experienced counsels see it as the least of the modifications. Still, I bought the pulley set for my LT1 and decided to leave the charging system where it was after reading a hundred posts or more. In the end, what really matters is how it makes you feel. I chose an airfoil for my throttle body instead.
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Old Nov 23, 2007 | 02:05 PM
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People have to understand....there is a downside to practically every single mod that we do (except maybe a lid).

Modifications are about compromise. The Upside vs. the downside. HP/Perforrmance vs Reliability/driveablity. What's acceptable for Joe-Bob, may NOT be acceptable for Billy-bob.

I have to say though, a pulley is one of the more mild mods performed and is considered to have very little downside. From my personal experience (not what I've "Read" or "heard from my cousin's brother's dad's uncle")...Out of the 3 different Fbodies I've owned, I've ran pullies on all 3, and have never had a charging issue or any negative side effect.

I wouldn't hesitate to recommend a pulley for a 6-8 rwhp increase.
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Old Nov 23, 2007 | 02:28 PM
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I have the 25% underdrive version and an overdrive pulley on my alternator. No problems.
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Old Nov 24, 2007 | 10:25 AM
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Originally Posted by Ebbsnflows
People have to understand....there is a downside to practically every single mod that we do (except maybe a lid).

Modifications are about compromise. The Upside vs. the downside. HP/Perforrmance vs Reliability/driveablity. What's acceptable for Joe-Bob, may NOT be acceptable for Billy-bob.

I have to say though, a pulley is one of the more mild mods performed and is considered to have very little downside. From my personal experience (not what I've "Read" or "heard from my cousin's brother's dad's uncle")...Out of the 3 different Fbodies I've owned, I've ran pullies on all 3, and have never had a charging issue or any negative side effect.

I wouldn't hesitate to recommend a pulley for a 6-8 rwhp increase.
Three of them - never had any negative side effect - wow. Guess what I "Read" from Billy-bob was wrong, then it really is an U P G R A Y E D D. Not Sure just got his *** a presidential pardon.
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