Underdrive pulleys, What manufacturer?

[m3f_BigmansM_4433bba443]

I have seen:

Evosport

Eurosport



both underdrive the alternator and something else



UUC

under drives the power steering and the alternator.

UUC seems to be the least expensive.

I just saw a post of a broken Eurosport pulley.

Any other opinions or options out there?



Should i just under drive my crank pulley instead? I dont think i have a lightweight flywheel in my future.



Im looking for personal experience opinions please.

[m3f_cstern_8f12f914a2]

I believe you can't underdrive the crank pulley because it serves as a harmonic balancer and pulley in one unit.


I'm not sure who makes the pulleys from VAC motorsports but I was looking at those myself

[m3f_BigmansM_4433bba443]

vac motorsports is claiming that their pulleys are their own.



what worries me and y I never did the pulleys upgrade is, underdrive the pulleys is going to cause some harmonic variances but, more importantly. the alternator and water pump should not really be under driven. the alternator needs to be pumping all the current it can, especially when the abttery gets old and doesn't hold or accept as large of a charge.

if the water pump is not turning as fast you will be more likely to over heat. I'm not saying its guarenteed but more likely...



I'm personally concerned with over heating b/c it has happened to me before. also I just did the fan delete so now I am even more likely to have an overheat.



what to do what to do?

[m3f_KnudsonsM3_69623f4ac6]

I like my UUC. Good Look and UUC makes quality Stuff.

[m3f_cstern_8f12f914a2]

I would prefer an underdrive including the crank to keep everything running in the same ratio, but not much of an option. I don't know these cars that well yet so I would say its up to the more experienced crowd to say if overheating or undercharging are issues to worry about

[m3f_thedood_4515c3f8d6]

overheating would be a big problem to worry about

[m3f_BigmansM_4433bba443]

overheating would be a big problem to worry about



Well would the under drive pulleys cause an overheat? or does it depend on the cars cooling setup?

[m3f_thedood_4515c3f8d6]

Well would the under drive pulleys cause an overheat? or does it depend on the cars cooling setup?



not really, i don't think anyone (manufacturers) underdrives the water pump. however, don't expect to fell much in the way of released power from pulleys. i'm not going to debate (search, there have been some epic battles), but the gains are minimal. this thread isn't about that, though. good luck!



PS- i would have picked Eurosport, but the recent malfunction (forum member) woulda worried me if i were in the market for such a thing.

[m3f_mx21]

Just my experience:



Not having any experience with crank pulley I cannot give you any info here and there is so much debate back and forth, it's a personal decision.



Having underdriven pulleys (waterpump, p/s but not alt-just lightened) and a fan delete (I did them at the same time) definitely frees up the revs but there is a trade-off. The cooling system is the weak spot under the hood and you have to be careful not to take too much away from the stock system.



After my ES power steering pulley failure and throwing the stock pulleys back on I think you are better investing money elsewhere. Not much of a difference.



If you are set on underdriven pulleys, I believe every kit underdrives the P/S and water pump with an option to underdrive or lighten the alternator pulley. I didn't believe you would get much benefit from the pulleys without removing the heavy clutch and stock fan. With both of these changes (pulleys and fan delete) you are now slowing the water pump and flow and also removing the primary cooling fan. In Texas this is too much for the cooling system in the summer and the solution is adding an electric fan (puller) or upgrading the radiator or both. The slim 16" fan that fits is a straight blade fan and very loud. It works well but also pulls about 11 amps - plus more when it kicks on. Add this to the A/C plus acc fan, headlights, fogs, any stereo upgrades, the heavy electrical load the car normally pulls and you are taxing the stock alternator. This increased load on a stock 80amp alternator can definitely be felt on the butt dyno so you are pretty much back to where you started.



As far as the Eurosport pulley failure, I wouldn't be too worried about it as I haven't heard of another failure but their customer service is terrible IMO.



So, in the end, U/D pulleys (not alternator), fan delete w/ additional electric fan, 140amp alternator, new radiator, optima battery. Make sure your cooling system is in top shape.



Better to spend money on suspension freshen - which includes all bushings or M50 manifold and kit - definitely makes the car more fun in the upper rev area.



Good luck - there are worse addictions!! eace:

[m3f_mx21]

I would prefer an underdrive including the crank to keep everything running in the same ratio, but not much of an option. I don't know these cars that well yet so I would say its up to the more experienced crowd to say if overheating or undercharging are issues to worry about



This doesn't make much sense - you would essentially be underdriving everything twice as much which would definitely create overheat and electrical problems in a D/D.

[m3f_cstern_8f12f914a2]

So if every pulley is 20% smaller, they don't remain in the same ratio relative to each other?

[m3f_BigmansM_4433bba443]

One issue that I am concerned with is:

the UUC pulleys are not lightweight, they are underdriven. So, my concern is, the pulleys may actually be heavier than the plastic pulleys in which they replace.


Although their technical information stats that the lightweight pulleys dont improve anything, this seems a bit understated.

decreasing the weight should decrease the load on each accessory.

Am i wrong to assume this? Am i wrong to be concerned with the weight?


I just want to know which pulleys are going to free up the revs a bit without hurting the chargin of the alternator.

[m3f_ths916m3_358ed6170e]

This doesn't make much sense - you would essentially be underdriving everything twice as much which would definitely create overheat and electrical problems in a D/D.



i like the avatar....where can I view it in full size?

[m3f_Ced]

lots of miss info in this thread...



http://www.uucmotorwerks.com/udp/udp_info/description.htm

[m3f_BigmansM_4433bba443]

hey guys. to bring this thread back to life.

I started a separate thread regarding an unorthodox crank pulley I bought. it is an obd1 pulley going on an obd2 car. will it work?

when I tried to swap the pulleys I noticed the bolts for the stock pulley are larger, and the pulley which connects to the ac belt is smaller.

I was under the impression that the ac is not affected by the ur pulley.



help