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Question on pulleys

614 Views 10 Replies 7 Participants Last post by  Codeman
Hey guys, Im a total engine newb. My expertise is in kitchen appliances and networking computers lol

I keep seeing sigs with pulleys in it. I did some looking up on Google and the logic seems sound. Seems like you can get the pullets for $200-$300.

Is there a write up somewhere or can someone explain to me what a different size pulley does? (meaning, in a 00 3.8L V6). I noticed unDrive and overdrive mentioned. If you get example the Jet pulleys...do you have to push that overdrive off button?

...again sorry, Im engine stupid on cars. I like paint and body mods.
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An underdrive pulley is on the crank, which is the source of power for all of your other accessories. By slowing having a smaller pulley on the crank, each of the accessories turns less per revolution of the crank. This is what frees up the power. An overdrive pulley is something that is used on one of your accessories, most likely the alternator. this is done to keep the voltage output up, especially if you have a big sound system in your car. Usually none of this is a problem though. And it has nothing to do with how you drive your car at all...other than ~10hp/tq.
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An underdrive pulley is on the crank, which is the source of power for all of your other accessories. By slowing having a smaller pulley on the crank, each of the accessories turns less per revolution of the crank. This is what frees up the power. An overdrive pulley is something that is used on one of your accessories, most likely the alternator. this is done to keep the voltage output up, especially if you have a big sound system in your car. Usually none of this is a problem though. And it has nothing to do with how you drive your car at all...other than ~10hp/tq.
...holy crap that made sense to me :eek:
i was wondering that to so glad u made this thread.

o and wow on the sig wataru
o and wow on the sig wataru

Domo!

Are you anywhere near Orlando, FL? There are 1996-2002 V6 Coupes all over from $2200 - $4000. Mine was only $5000. There's a 1998 V6 SN96 laser red with 105k miles right up the road in Longwood for $2795
Another question gentleman. Ive been hearing from people that going to UDPs for a V6 wouldnt acutally help. I heard itll cause your engine to run alittle hotter and cause your alternator to slow down and your battery will die faster....? Avoid it daily driver.

any truth to this?
well it does add some power. I noticed a change in performance when i put mine on. As far as the overheating my car has not overheated and i have been on it autocross racing and it has not overheated. I have noticed that when I have my headlights on with my fog lights, my gauge lights, and my radio that the lights dim. But for the average person that is not really going to happen. I mean with just my headlights on and the radio at a normal level the headlights do not dim. It does reduce the output of your alternator so if you have a big stero system it will cause your battery to go dead and not get charged because you will be maxing out your alternator.
I have had a UDP on my V6 for over 3 years now, and still have the same battery,and have not overheated yet.
well if ur lights are dimming with a udp that's when u can looking into getting a overdrive pulley for the alternator
I just recently got some on, and it really made my car a completely different car. Not so much the power, but when i shift now, its so much smoother. So far i am very pleased with them. Have only had them on for a week or so, but i havent had any problems.
i know i need an overdrive pulley for my alternator. where is a good place to find one? and do i need any special pullers or will just a normal puller work?
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