Underdrive pulleys

ok were are the underdive pulleys at are they the pullyes right on your engine the things connected to your belt. or is it actully under the car. and are they good to get. and how do i know if i already have them. thanks help me plaese. im a newby at this.

LOL they are the pullies that are run by the crank and the belt.

It's hard to tell if they are underdrives without having stock pulleys to compare to. Maybe there's an easier way?

ic, mine are black does that help, what is the diffrence of stock pullyes and underdriven pulleys.

Stock pulleys are different sizes. Usually there's 3, the Crank Pulley, the Alt Pulley and the Water Pump Pulley

The crank pulley is smaller than the stock one, and the others are bigger than stock. That way the Alt and Water Pump spin slower and don't put as much stress on the engine. Also they are lighter (mine are 6lbs lighter than stock) so there's less mass for the engine to spin. All together help you to get maybe 6-10hp. It's definitely worth it as a way to start modding.

thanks, but what if i want the alt to spin more. i have some pritty big subs in my car, they need to be powered. i just bought a new 200 amp alt for my car i have put it on yet it came with a pulley on it should i change it or keep the one it came with one.

Probably better to leave the one that's on there.

i did a 3g alternator on my car, used the pulley that came with it since the one in my underdrive set is the same size. no charging problems whatsoever. i also used a 4ga. charging wire kit from PA Performance, in order to save the stock wiring.

thanks, but what if i want the alt to spin more. i have some pritty big subs in my car, they need to be powered. i just bought a new 200 amp alt for my car i have put it on yet it came with a pulley on it should i change it or keep the one it came with one.

my friend runs a competetion system of 4 12's in his escort with the stock alt, all he did was get a overdrive pully for it. Not a single problem.

I'm also running underdriven pulleys, 3 12's and 6 other speakers, and a stock 90' alternator. The biggest problem I've run into so far was sitting around with the car off, and the speakers goin, the headlights dim a bit when the bass hits. I think you'll be ok. (This is not including the many other electrical problems my fox suffers, lol)

ic, now if i were to get a supercharger i would get a overdrive pulley kit. So underdrive pulleys make the other thinks spin slower and overdrive pulleys make the thinks spin faster. is that.

well ill be running 2 12s at 1800 watts rms in to each sub.

and how hard is it to put these pulleys on, also do i have to get a new belt or something.

to put them on you need to use a impact wrench to take off the pully on your alternater{take the whole alternater up to pep boys, theyll do it fo free} then the water pump pully whould come off with a wrench with a pipe on it for some leverage. the crank pully needs a puller to get seperate it from the motor. the best thign to do is jack the front of your car up and do it from under neath. the puller can be found at an auto zone or stoer of that nature it looks like a ducks foot and should not be very expensive.

to put them on you need to use a impact wrench to take off the pully on your alternater{take the whole alternater up to pep boys, theyll do it fo free} then the water pump pully whould come off with a wrench with a pipe on it for some leverage. the crank pully needs a puller to get seperate it from the motor. the best thign to do is jack the front of your car up and do it from under neath. the puller can be found at an auto zone or stoer of that nature it looks like a ducks foot and should not be very expensive.

alt pulley can come off if you use a long-ass screwdriver to hold the fan still.

crank pulley comes off with a hammer from behind

water pump pulley comes off after the fan, and can be wiggled free

i speak from experience =D

also, leave the belt on while you loosen the bolts and alt nut, and put the car in gear w/ hte parking brake on while you do the crank bolts.

ok so it should not be to hard then.

Silly question? Does anyone get any problems with their cars overheating in the summer after changing there underdrive pullies? I live in Las Vegas where in the summer it can reach up to 120 degrees. Damn that's hot!!