ebay pulleys

[okinawa drift]

ok so im not sure if anyone has any experience with buying pulleys off ebay, but i don't really see what could go wrong... the price is just too good

whats the difference between this

http://cgi.ebay.com/ebaymotors...ories

and megan? they both look the exact same

[OM3GA]

If you want to go cheap go with ISIS, Megan or Circuit sports, I wouldnt go any cheaper than that.

[allenms240]

Hmmm, I heard aftermarket lightweight pulleys were bad for or motors, whether a KA or SR. I read in a magazine that some motors are balanced externally with whats on it, including the pulleys, and if its lighter it will throw it off and possible ruin the motor. If I were you, I'd do more research before buying em.

[okinawa drift]

Hmmm, I heard aftermarket lightweight pulleys were bad for or motors, whether a KA or SR. I read in a magazine that some motors are balanced externally with whats on it, including the pulleys, and if its lighter it will throw it off and possible ruin the motor. If I were you, I'd do more research before buying em.

interesting....

[OM3GA]

That has nothing to do with the accessory pulleys. Sure they need to be somewhat balanced to not destroy the bearings in your accessories (why i said go with the megan,isis,circuit sports if you want cheap) What Allen is referring to would be the Crankshaft pulley aka Harmonic balancer device.

People are getting their crank pulleys confused with the harmonic dampers found on some domestic V6 & V8 engines. "Harmonic Balancer" is a term used loosely in the automotive industry. Technically, this type of device does not exist. The "balancer" part comes from engines that are externally balanced and have a counterweight cast into the damper. None of the applications we offer use a counterweight as part of the pulley, as these engines are all internally balanced.

The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley making them look similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress noise from the engine accessories; the A/C compressor, P/S pump, and alternator. This is what the manufacturers call NVH (Noise Vibration & Harshness) when referring to noticeable noise and vibration in the passenger compartment. It is important to realize in these applications, the elastomer is inadequate in size and durability to act as an effective torsional damper. If you look at the pulleys on some imports there is no rubber to be found at all. We have samples of these, mostly from Acura/Honda B & D Series engines, Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's just to mention a few. Most owners who have installed our pulleys notice the engine actually feels smoother. This is result of replacing the heavy crank pulley with our crank pulley. NVH is variable and unique to every car. NVH will increase with the installation of an aftermarket intake and/or exhaust, for example. Think of OEM intake systems in newer cars, they use baffles and resonators in the intake to quiet all the intake noise. Aftermarket intakes eliminate these resonators and create dramatic increases in engine noise from the throttle opening and closing. So to most tuners, certain types of NVH can make the driving experience more enjoyable.

The purpose of a traditional harmonic damper is to protect against crank failure from torsional movement and frequencies of high amplitude. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as shorter stroke length, smaller displacement, piston dwell time, piston pin off-set, power output, etc., do determine when and how these harmonics and torsional movements occur. More importantly the actual tune of the engine, espcially with modified vheciles, is the biggest factor in potential engine damage. Poor tuning leads to detonation which is an engine killer that no damper can stop.

[Razi]

Keep your stock crank pulley, you can replace everything else if you wish.

One of these "lightweight pulley" things on your crank can increase crank vibration and be bad for your motor.

[jeff420]

the last 2 posts contradict eachother lol. ive heard of people running lightweight pullies without any problems whatsoever. sure if someone spun a bearing it would be easier to blame it on the pully than the fact that they were driving like an a$$ when it happened.

[OutToWinPAHC]

Keep your stock crank pulley, you can replace everything else if you wish.

One of these "lightweight pulley" things on your crank can increase crank vibration and be bad for your motor.

This or a quality SFI rated harmonic balancer. Pulleys are bad news unless they are balancers of quality.

[okinawa drift]

hmmm really good info, i bought my motor with a megan racing crank pulley, should i take it off and put a stock one on??

[KA-T S14.5]

I hate this stigma around lightweight pulleys... In the G35 world they warn against them like they are the devil's work... BUT people run them with no problems and the only real reason that I have found that a Pulley is at fault, it was only at fault because it voided the warranty on the motor when a camshaft went crazy and popped the motor. AND it is pretty hard to mess up creating a pulley... It is basically void of error because the entire process of making them is them getting spun in a perfect circle as it gets milled down. AND I agree with Jeff420, people will find any reason to blame a part over bad driving, OMFG I was running mah stock motor at 8600rpm and down shifted, and because I have an underdrive pulley, my motor blew....

[OutToWinPAHC]

Bad info..... Please do you homework on the issue. The KA is a half balanced motor as it is, so changing to a non stock or non hormonic balanced pulley will induce even more vibaration onto the crank. Overtime it wears bearings causing oiling clearance issue, exspecially at higher RPM's. All roads lead to premature bearing wear.

Stock or this http://www.phase2motortrend.com/atiendadoka.html

[okinawa drift]

but as far a SR goes, does this apply to the SR too?

[OM3GA]

It applies somewhat to the SR as well, more so to longer crankshaft motors. However the ka is also affected. I ran one on mine but i was just trying to squeeze every bit of power out of my NA setup regardless of how long it would last. I drove it a good 5-8000 miles probably with that pulley on there.

However if you care about your motor enough id stick with a stock crank pulley or an ATI unit. I have even heard things about the ATI one affecting the crankshaft vibrations in negative ways but no proof behind it.

Either way i wouldnt go with a full aluminum pulley, i almost did but i ended up buying a brand new oem one for my crank.

Anyways back on to your Original topic OP the aluminum pulley Acc. Set, you should go with one of the brands i mentioned dont cheap out on something when youre already considering the cheap route.

You can not keep copying copies you'll eventually have a worthless pos.

[White Comet]

too much heresay and theory in hear, some real experiences would be nice. i personally have similar pulleys to whats posted in the first post and dont foresee any problems with them. as for the crank pulley, the sr and the ka are ones that dont really need to worry about vibrations from an aftermarket crank pulley. i had a UR crank pulley on my ka and loved it, i will be doing the same for my sr when i get around to it