goredcar

I had ordered a set of Unorthodox Racing underdrive pulleys from a performance shop... and it took forever to get to me, but now as I am about to arrange installation, I am told by the mechanic that he really does not recommend it. Reason being that our stock crank pulley has a plastic dampening ring which absorbs any resonant vibration at highh RPM.

The UD pulley is solid and gas no ability to absorb resonant vibration, passing it on to the engine, resulting over time in loosened bolts and other bad stuff. Bottom line is that he didn't recommend it, and said that the risks were too great for matginal gains.

So... two questions... has anyone had problems? and the second question... are there noticiable gains?

Excelerate

iTrader: (1)

Here is a link to long thread about the UR pulleys.

http://www.acura-cl.com/forums/showt...rthodox+racing

If you search, "unorthodox racing" a bunch of threads come up.

Rod

Do a search, this subject has been beaten to death. Although I believe no one with a CL has had any problems, I wouldn't get them, but that's just me. People on the forum have been using for a while with no problems, but if there are any negative consequences they are long term and I don't think anyone's had them long enough to really judge their effects, unless you open the engine up.

flint

iTrader: (2)

check UR's website on this issue

mrsteve

iTrader: (1)

4) "Is my crank pulley a harmonic/torsional/vibration damper or a harmonic balancer?"

People are getting their crank pulleys confused with the harmonic dampers found on some V6 / V8 engines. "Harmonic Balancer" is a term that is 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, hence the merging of the two terms. None of the applications that we offer utilize a counterweight as part of the pulley as these engines are internally balanced.

The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley that looks similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress natural vibration and noise from the engine itself, 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 note that in these applications, this elastomer is somewhat inadequate in size, as well as life span, to act as an effective torsional damper. If you look at the pulleys on some of the imports there is no rubber to be found at all. We have samples of these, mostly from Acura/Honda, the Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's, to mention a few. This is not to say that with our pulleys you will hear a ton of noise or feel more vibration from your engine compartment. Most who have installed and driven a vehicle with our pulleys will notice the engine actually feels smoother. This is a natural result of replacing the heavy steel crank pulley with a CNC-machined aluminum 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. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as stroke, displacement, inline, V configurations, power output, etc., do determine when and how these harmonics and torsional movements occur.

Again, there is a lot of internet hearsay about the pulleys. When engine problems occur, too often people are quick to blame the pulley first, rather than taking the time to look logically into why there was a problem. We hope that after reading this you will understand the crank pulleys better.

dj5

For me the gains on the UR pulley don't outweigh the risks. I will not be installing them on my TL-S as I plan on keeping it several years.

Seattle Cl-S

The gains are not marginal. Look at the dyno for the CL-S on their website. Gains are significant and throughout the entire RPM range. My engine feels smoother and revs much quicker than b/f.

NSXNEXT

iTrader: (2)

One of my best performance mods. 2nd to headers.

mattg

i've had them on my car for a couple years now w/ no problems. the car stilll runs smooth.

they were installed by my acura dealership. the techs didn't see any problem w/ them.

mattg

the mechanic is right about there being a rubber layer in the stock crank pulley.


i just figure if i smoke this motor it's 3.5L time.

blader

I've also been thinking about this mod .. any other input from people who have the pulley?

goredcar

So... there are no warranty implications?

goredcar

Thanks... the dyno charts show that the gains are not marginal... the torque curve is the most interesting as improvements are across the entire RPM band. This might be a really nice complement to fill in the gap before the headers kick in.

I am still a bit worried about long term effects though as I plant to keep the car for several years... any thoughts?

TopGum

The dealer installed mine, twice actually. The did the underdrive pulley and then when I installed the SC, I replaced it with the UR Sc pulley. No one ever mentioned anything negative about it. So, if the dealer is ok with it, so am I.

blader

I think there is someone on here who's had them for like 40,000 miles with no problems on multiple cars.

Also .. is there anyone that just runs the UR crank pulley and not the PS and Alt pulleys? Do you have to do them as a set or can you just do the crank?

Chaptorial

I've had them on now for about 1/2 a year so far and no problems to speak of.

farberstyle

18000 miles later and no problems. if there are to be problems, they will not show up for at least 100000 miles or more. I f you are super-paranoid (and i dont mean regualr paranoid), send your used motor oil in for analysis every 5 changes to see if there is any damage. but to echo the rest, i enjoy the pulley very much, and enjoy the better gas mileage and performance.

Louie11

I have just the crank pulley. You can install the others at a later date if needed. The others are more cosmetic so I didn't feel like spending the money. Otherwise I have had mine for about 20,000 miles and I love it. The revs sure do come up faster.

goredcar

Thanks everyone... I really appreciate the input. I am torn, on the one hand I would really like to fill the gap before the headers kick in, but I am not keen to make any long term compromises.

I will think on it some more...

Thanks again for all your help!

Chopsie

You keep mentioning the "gap when headers kick in", there is no gap, headers give more power throughout the powerband.

mrsteve

iTrader: (1)

Not really. I've experienced no gains up until about 4500 rpm. This is on par with Comptech's dyno too: http://www.comptechusa.com/images/dyno/2000CLSplot.pdf

goredcar

Yup... I have to agree with MrSteve... I was actually pretty dissapointed that the headers did nothing till high RPM... 4500 sounds about right. I was hoping for some torque increases but they are minimal. With intake and headers there is definately a gap (weak spot) in acceleration till you hit VTEC and then the intake and exhaust optimization really pay off.

I guess that it makes sense... all headers do is optimize airflow... so the effect that they would have would be minimal till the engine is pushing a lot of air.

I friend of mine who is a Honda mechanic had a good analogy... he said that an engine is basically an air pump... the more air you can get in and out, the more power you get.

sgmotoring

Can anyone tell me who have the best price for a SSC unorthodox pulley?

Chaptorial

Velocity can do it for around $215 shipped. That's where i got mine.

MSRP $268