Underdrive pulleys?
Safety Car
Joined: Jun 2000
Posts: 4,870
Likes: 25
From: Long Island, NY
Re: Underdrive pulleys? (BobMachus)
Vic '89 seems to have documented some good results, there are others I don't remember who just now tho.
It should be good for a solid 1 tenth in ET.
The cons are the alternator will not fully charge the battary at an idle with the headlights on and the AC also on. Other than that , there seem to be no issues. As soon as you start to move, the battary will go above 13 volts.
Vic
Drifting
Joined: Aug 2001
Posts: 1,606
Likes: 14
From: Vacaville, CA
Re: Underdrive pulleys? (KYVette90)
I installed the underdrive pully's and felt a noticible gain in performance. The bottom crank pully is a little tough to get at and requires some patience. I used the March brand of pully's, one of the better known brands. My alternator survived for ten years this way and finally burned out. :lol:
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Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Underdrive pulleys? (Glock'94)
Sounds like I will have to get one while I have it ripped apart (documented in "The Project" post). Installing the balancer tomorrow. Sure would make it easier :cheers:
Team Owner
Joined: Nov 1999
Posts: 32,782
Likes: 11
From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Underdrive pulleys? (KYVette90)
The mod is not worth the gain. :nonod:
Pro
Joined: Mar 2001
Posts: 602
Likes: 1
From: Hacienda Heights, Ca. USA
Re: Underdrive pulleys? (KYVette90)
Use the March Performance "Power and Amp" series pulleys. It's a three peice set, crank, H2O pump & alt pulleys. The alt pulley is made to compensate for the reduction at the crank. Your charging stays the way it should. And yes, you will notice a difference in sotp driving and it is a worthwhile change. :D
Racer
Joined: Oct 2000
Posts: 476
Likes: 0
From: Socorro New Mexico
Re: Underdrive pulleys? (KYVette90)
I've had one on mine for 5 or 6 years now. I picked up a couple miles per gallon, that has to translate into something. Never experienced P/S, AC, temps or charging problems. Well the volts do drop below 13 at idle, but who does much of that.
I have a friend who likes to backpack, his philosophy when filling his pack for a hike is, "Take care of the ounces and the pounds will take care of themselves." I think that that notion applies to hot rodding as well. Not every improvement will give you 20 horsepower. To catagorically relegate a small increase to waste of time is counter productive. Spending a $1000 for 1/100th of a second would be dumb (for the street) but $100 bucks or so for ~ 1/10th of a second here and there; absolutely.
I think that my crank pully was a wise investment :)
I have a friend who likes to backpack, his philosophy when filling his pack for a hike is, "Take care of the ounces and the pounds will take care of themselves." I think that that notion applies to hot rodding as well. Not every improvement will give you 20 horsepower. To catagorically relegate a small increase to waste of time is counter productive. Spending a $1000 for 1/100th of a second would be dumb (for the street) but $100 bucks or so for ~ 1/10th of a second here and there; absolutely.
I think that my crank pully was a wise investment :)
Melting Slicks
Joined: Dec 2001
Posts: 2,049
Likes: 0
From: Texas
Re: Underdrive pulleys? (Rynda)
I've heard of people using pulleys with both good and bad out comes...
A while back there was a post about LT1/LT4 pulleys, I think it was basically decided from those who DID post in that, that pulleys were not worth the money. I've opted not to get pulleys when I start buying parts for my car. :seeya
As you can see though some people gain, I've never had any myself, good luck.
A while back there was a post about LT1/LT4 pulleys, I think it was basically decided from those who DID post in that, that pulleys were not worth the money. I've opted not to get pulleys when I start buying parts for my car. :seeya
As you can see though some people gain, I've never had any myself, good luck.