I'm picking up a set of Unorthodox Racing Ultra SS Pulleys (accessory pulleys + crank pulley). In another thread somebody told me that this would be a BAD idea since the Unorthodox crank pulley doesn't have that rubber dampener that the stock crank pulley has...which leads to crankwalk. Is this a fact? My car has always run well and I don't want to cause any crank issues.

I would stay way from putting one on, I've always been told its a no-no.

Your crank pulley will not effect your chances of getting crank walk. People will probably argue otherwise but they are morons and are paranoid of crankwalk. Thrust bearing failure is due to lateral load on the crank. A pulley will provide no such load.

The rubber dampener is just that... a dampener.

does it cause crankwalk? no

does it increase the vibration going to an already poorly designed crankshaft? yes

its up to you

The Harmonic balancer will not cause crankwalk nor does it balance anything, it's there to reduce the twisting action of the crank, to un-crank the crank if you will. It's often hard to gauge whether a non-dampener pulley is damaging because it's often an indirect and a long term process. It's much easier to ask instead "Will an UDP produce a noticeable performance difference to justify the risk?", until someone shows me a back to back dyno numbers, my oppinion is "no".

Thanks for the feedback, I trust you guys know your stuff...I get mixed thoughts on this subject all the time. I figure I'll try the pulley kit since I'm getting it for only $175 (vs. $400+ retail)...if I screw up my engine, I'll get a 6-bolt. Peace.

"Letter from Dave Buschur to Talon Digest Sept. 1998

Hello, I am not starting a debate again. As a matter of fact, if you have some questions send me a private e-mail. I do have some facts though. First let me say, yes, I have been running an Unorthodox underdrive pulley for about a year. I have had no problems that I can blame on the pulley, they are nice and they are cheap. If they do pick up 10hp like Turbo Magazine says they do then they are a bargain. Now to my point. As alot of you know I have been working with a company to have some custom dampers done with the underdrive built into them. They are finally done and I have done the final testing. We have had the first unit on and off the AWD a few times to get results back and the final settings have been made. After looking at the unit and getting the feedback from the shop that is building the units for us there is ABSOLUTELY NO doubt that these cars, just as we thought, have to have the damper on them. I have had some unusual bearing wear for the last year or so. The more I learn about dampers the more I understand that the problem was 99% related to the fact I have not been running one. We did end up keeping the underdrive unit in the damper too. So there is less drag and we get a superior damper compared to the stock unit. Now, everyone that has ever bought a performance part thinks it works, why? Well you just spent your hard earned money on it. I have done the same thing in the past I am sure. I am very skeptical nowadays. Well I took the damper off the AWD Sunday and put it on the RWD. Since it is the only one I have so far I wanted to swap it. The difference? Holy $h!t. The RWD engine is mounted to solid aluminum plates which are bolted directly to the frame of the car. The car vibrates so hard it goes up your spine, it also vibrates enough to readjust the rearview mirror just revving the engine. I cannot believe it but this is all but gone. I mean you can still feel the engine has some vibration, it has to mounted this way, but the majority of it is gone. I am going to be really curious next time we pull this engine down to see what the bearing look like. I have 10 more being shipped to me ASAP, they are built, the shop and I are just working out pricing. The first 7 are sold. This is the list of the guys first names (for privacy), you guys will know who you are, if you have changed your minds please contact me. I have three more available."

Interesting...who here uses aftermarket pulleys?

i used one....no problem with it....hrmmm...

g_ferg said:

i used one....no problem with it....hrmmm...

Click to expand...

According to your profile your on a N/T, which would make this a whole 'nother story. Two totally different engines. The 420A is not even known to crankwalk, which makes it no problem or worry for them.

So there are a lot of theories and hypotheses about crankwalk, dampeners, pulleys, etc. Who has had any problems with aftermarket crank pulleys?

lets put the whole "crankwalk" deal aside. It's been shown to create improper bearing wear.

How about if I threw in a Moroso Oil Pan, which hold 2 additional quarts of oil-would that help prevent this issue of bearing wear?

no way to tell i dont believe anyone has done that before, due to the fact that it might cause botom end failure. but if someone has then i stand corrected, but i do not see 2 qts more of oil helping bearing failure.

I am currently using the entire ## ss set. I have not had any issues at all. Also I have noticed a difference in the rev speed of the motor. Due to the lower rotational mass, the motor will rev faster. As for bad for the bearings....I think not. The only added vibration will be from the movement of the belt and the accessories. Lead to crankwalk...in my opinion, no.

Awesome, how long have you had the pulleys installed?

OK. Now, does the fact that I am installing a balance shaft eliminator kit contribute in any adverse way to this issue? From what I understand it's (balance shaft) there to help dampen the vibrations that the engine causes (mostly between 2k-3k rpms).

I also have the b/s gone. I notice a little vibration, but nothing outragous. My car revs like a bat out of hell though. I believe that the pulleys help. But I have the whole set not just the crank pulley also. Plus no A/c

Just out of curiosity, did you remove the balance shaft yourself? Also, what pulley kit do you own and how long have you had it installed?

Yeah I did the b/s myself. I have the ## ss set. I've had them in since dec 04

I think a lot of you get confused here. This is not about the kind of vibration you feel when removing counter balance shafts or the balance of the crank and internals but a twisting motion in the crank as it deflects under load.
This unchecked harmonic oscillation of the crank can and does lead to premature fatigue failiure. If your crank has been turned down and the fillets aren't perfect, you could be in for trouble but "your mileage may vary" strongly applies.
Been there, done that and in hindsight I feel it was stupid on my part to fit a undamped pulley on my car.My opinion (as a former user) is that the underdrive pullies like the U/R piece are a straight-up ricer mod. If you want to lighten up your rotating assembly, get a Fidanza flywheel.


http://www.fluidampr.com/problem.htm

dsm_illicious said:

Who has had any problems with aftermarket crank pulleys?

Click to expand...

Me....

This may not have anything to do with anything but on my subaru it has had a Unorthdox racing UD pulley for minimum 3 years and no problems at all. over 40k miles on it.

It's on my daily driver. The rev limit is 8,500. The motor only had 11,000 miles on it before the crank broke.

Well, I'm glad I read that Fluidampnr (or whatever it is) post, I've opted to not purchase the UDR pulleys...hopefully Flluidampnr will come out with a pulley/dampener soon! I e-mailed them asking if & when, everybody else should too-maybe they'll hurry it up!