underdrive pulleys do they work???
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Instructor
Joined: Aug 2000
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From: philadelphia,pa pa
underdrive pulleys do they work???
I see march has an underdrive pulley set for lt 1 and I was wondering if it even works for the lt1 heres why. I understand the concept of underdrive pulleys and I dont see where its a benifit for lt1's.First of all the water pump is driven off of the cam gear so the water pump is out of the picture all together.The a/c (if it is off )is just a free wheeling pulley so that is out of the picture. Next is the power stearing pump. Now I am not sure on this one but I thought it was only taking power to run power stearing when you are turning.Last is the alternator which definetly takes power to turn, but the march kit gives you a new pulley for the alt. to compensate for the underdrive crank therefore canceling out the benifit of the underdrive.Am I right in my thinking? has anyone tried these?are they worth it? thanks for your input. Rich
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From: Former NCM Drag Racing coordinator, National director Corvette Challenge Spring Hill, Tennessee: Whiting, New Jersey
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Never liked these, a fully charged battery is more important.
Race Director
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From: oregon
only useful on high rpm engines when you have a problem liquidating alternators. most the time you can just up the size of your alt pully and accomplish what you need to. L98s for example will roast alternators fairly quickly if you spin 6500rpm or more and have a stock size pully.
Melting Slicks
Joined: Jul 2003
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From: Canton MI
only useful on high rpm engines when you have a problem liquidating alternators. most the time you can just up the size of your alt pully and accomplish what you need to. L98s for example will roast alternators fairly quickly if you spin 6500rpm or more and have a stock size pully.
Safety Car
Joined: May 2004
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From: Naples FL
The real question is why do you think you need these underdrive pulleys. There's very little gain and you risk a dead battery. I only see a downside here.
March is about a half mile from my house and I've found that they aren't very helpful. I asked them for a pulley set for my track car. I don't have an air pump and no a/c. They tried to sell me a stock set of pulleys and had no interest in helping me.
That made my decision real easy.
Richard Newton
101 Projects for Your Corvette 1984-1996
Autocross Performance Handbook
March is about a half mile from my house and I've found that they aren't very helpful. I asked them for a pulley set for my track car. I don't have an air pump and no a/c. They tried to sell me a stock set of pulleys and had no interest in helping me.
That made my decision real easy.
Richard Newton
101 Projects for Your Corvette 1984-1996
Autocross Performance Handbook
Le Mans Master
Joined: Jun 2006
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From: One day you're a Comet...the next day you're dust... Arkansas
I see march has an underdrive pulley set for lt 1 and I was wondering if it even works for the lt1 heres why. I understand the concept of underdrive pulleys and I dont see where its a benifit for lt1's.First of all the water pump is driven off of the cam gear so the water pump is out of the picture all together.The a/c (if it is off )is just a free wheeling pulley so that is out of the picture. Next is the power stearing pump. Now I am not sure on this one but I thought it was only taking power to run power stearing when you are turning.Last is the alternator which definetly takes power to turn, but the march kit gives you a new pulley for the alt. to compensate for the underdrive crank therefore canceling out the benifit of the underdrive.Am I right in my thinking? has anyone tried these?are they worth it? thanks for your input. Rich
Last edited by BADDUCK; Mar 24, 2008 at 09:52 AM.
Drifting
Joined: Oct 2006
Posts: 1,934
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From: Citrus Heights California
You can get the March Power and Amp type under drive pullys. I have a set. The alternator pully is a little bigger. It charges fine. I threw away my frisbee. I installed an Edlebrock polished aluminum water pump. I also installed polished aluminum March pullys and a chrome high out put alternator. I just wanted to give it more bling. But I swear the Vette performed better. It's been on about 2 years with no problems.
Last edited by Kool88vette; Mar 24, 2008 at 10:22 AM.
Team Owner
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From: San Antonio Texas
I think you're right about not being much benefit on an LT1. I had a full set on my GT Mustang and I really could feel the difference, but the belt ran everything on that engine. I could barely drive it at nite becuse the lights would go so dim at a stop. I had to switch back to the stock Alt. pulley to speed it up, but then had problems with the tensioner not working right. It was hardly worth the hassle, and would probably a waste of time and money on an LT1.
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Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
only useful on high rpm engines when you have a problem liquidating alternators. most the time you can just up the size of your alt pully and accomplish what you need to. L98s for example will roast alternators fairly quickly if you spin 6500rpm or more and have a stock size pully.
