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Discussion Starter · #1 ·
Hello all, I have purchased a direct fit replacement clutch from UUC, it is has 150% more clamping force then OEM and the friction material is uprated from that of OEM. My stock clutch began slipping at 18000 miles and the dealer said they were going to replace it but long story, gave me the run around and lied to me and gave me the car back the sameday I was moving out of state and said basically, by the way we never replaced your clutch, so for the last year I have been running the same clutch, which still slips under heavy acceleration, and I have I now have 36000 miles on the car and the clutch still works. So my rationale was basically the stock clutch works for me 90% of the time since I do not drag race or track my car, its just my daily driver, I thought the V-12 conversion kit was probably overkill and it was hard for me to justify a 3000 dollar purchase. So when Rob at UUC suggested I try this new clutch, I thought what the heck, if I can get 36000 miles out of an OEM clutch, hopefully the UUC design will satisfy my needs of both longevity and superior performance over OEM. I am having it installed friday at Bavarian Hypersports in Houston. So I will be able to provide feedback to those who want a better clutch then OEM but dont need the V-12 conversion. It also provides an alternative to spec clutches, so I hope it all works out and hopefully we as owners will have another clutch option. Also I forgot to mention it is substantially cheaper then the V-12 kit, I believe it is priced close to that of an OEM clutch, Josh

P.S. I am also having the EVO 3 and DSSR rod installed at the same time, should be a good day this friday. Thanks for for your help Rob and the UUC crewcherrsagai
 

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Great to hear that that option is out now Josh. We were discussing this ont he thread with Rob's input a few weeks back, I didn't realize the package was out now. Did you decide to go with the rogue LW flywheel or a new OEM dual mass? My only concern with the LW options would be the chatter it would create so I'm VERY curious to see what your settled on solution turned out to be for that (though I would definately love the benefits of a quicker revving drivetrain). Same as in the last thread, I'm in the same boat as you except I've got ~55,000 miles and it's time to look at replacements. I'll give Rob a call and talk to him also, just curious as to what your solution was...definately keep us posted next weekend and through the break in!

:cheers:

Sean
 

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Gustav said:
Interesting. We expect a review :)
You'll be getting two soon. ;)
 

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What is this? Did UUC drop the 850i replacement kit? I'm coming up on clutch replacement soon so am starting to think about the various alternatives. I was set to get the UUC upgrade kit but was a bit hestitant about possible rollover noise. I'm skeptical about a simple replacement, however, because the stock size is so small.
 

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Keep us posted, I have 42k on the original clutch and it's definetly seen better days:noSMG:
 

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Need4Spd said:
What is this? Did UUC drop the 850i replacement kit? I'm coming up on clutch replacement soon so am starting to think about the various alternatives. I was set to get the UUC upgrade kit but was a bit hestitant about possible rollover noise. I'm skeptical about a simple replacement, however, because the stock size is so small.
No, they still have the 850 setup. This is a performance version of the stock sized clutch that mates to the stock flywheel. The SAC mechanism is gone (thankfully), so it is a great choice for those that were planning on just using a stock replacement again. If I drag raced my car a lot or tracked it all the time, I would definitely go with the larger sized 850 solution.

Here is a direct link to their direct fit info.
 

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How's this differ then the SPEC offers? DOn't they have an organic disk as well?
 

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I'm very interested in feedback on this product as I will be considering it soon.
 

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Yes, please post results of this clutch swap. I will be in the market for a clutch in the next year, and am a moderate driver, so this sounds like a good alternative. Also, what is the cost of this setup?

Eric
 

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Discussion Starter · #12 ·
Sorry for the delay, I have been on the road, looking for a house in jacksonville, but as others have said this is simply an uprated version of an OEM size clutch, it provides more clamping force and better friction materials. I am using the stock flywheel, so all I am hoping for is better then OEM performance, I know that it will not be the same as the V-12 kit, but as long as it is as good as a performer then OEM if not better, then this is what I was looking for, the cost is about equal to what an OEM clutch would cost anyways, so I figured I had nothing to lose. Will be installed this thursday or friday, to be determined tommorrow, BHS has alot of work going on their right now and they have to fit me in. On a side note I got to drive S/C Kelleners or maybe phillyM5 car up to houston, 2XX mile trip and it was a blast, and while dropping the car off with the owner of BHS he had a Imolia red M5 in his possesion and he said he was about to do some high dollar mods to that car, just wondering if it is a fellow board members car, I am sure it will be pretty cool when finished, will keep you all posted, Josh
 

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Need4Spd said:
What is this? Did UUC drop the 850i replacement kit? I'm coming up on clutch replacement soon so am starting to think about the various alternatives. I was set to get the UUC upgrade kit but was a bit hestitant about possible rollover noise. I'm skeptical about a simple replacement, however, because the stock size is so small.
No, the 850CSi V12 conversion flywheel and clutch is definitely not being replaced! (The fact that we can't even keep them in stock is part of that... :D )

However, we recognize that not all M5 owners are looking for a lightweight flywheel, nor use the car in such a way that they would require the large 280mm V12 clutch... nor do they want to rush right out and spend $3K on these components. They may simply need a new clutch, and that's all.

The UUC Direct Fit clutch for the E39 M5 is designed specifically for that kind of M5 owner, as a Performance/Replacement unit to work with the original flywheel (or even any lightweight flywheel that was designed for the M5 clutch in the first place).

But as usual, there are a number of significant advantages with the UUC Direct Fit clutch:

1) All-new pressure plate without a Self Adjusting Clutch (SAC) mechanism. That means much better clutch feel and no SAC-caused reliability concerns.

2) Much greater clamping force and uprated material - although there is no increased pedal effort and the engagement feel is nice and smooth just like the OE clutch, the power capacity of the unit is much higher.

3) Sprung-hub center - for those of you with other-brand lightweight flywheels with solid-hub centers complaining of rollover noise / gearbox rattle, the UUC Direct Fit clutch will greatly reduce and possibly eliminate that sound.

Hope that helps clear things up!
 

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Rob,

Since there is no increase in pedal pressure but there is an increase in clamping force, I assume this is achieved with greater mechanical advantage in the pressure plate itself somehow? Also, I assume I could order this unit and have my local BMW dealer install it, and my tech would not experience hardly any difference in the install process compared to the factory unit?

Thanks,
Chuck (finger on the buy button)
 

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Rob Levinson said:
But as usual, there are a number of significant advantages with the UUC Direct Fit clutch:



3) Sprung-hub center - for those of you with other-brand lightweight flywheels with solid-hub centers complaining of rollover noise / gearbox rattle, the UUC Direct Fit clutch will greatly reduce and possibly eliminate that sound.
Rob
Can we then be assured that if we go this route and do NOT use a lightened flywheel there will be NO rollover noise, just like stock??
Thanks.
Regards,
Jerry
 

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CSBM5 said:
Rob,

Since there is no increase in pedal pressure but there is an increase in clamping force, I assume this is achieved with greater mechanical advantage in the pressure plate itself somehow?
Correct. This mechanical advantage is achieved within the same total pressure plate space due to two factors:

1) Space regained that is normally used for SAC mechanism allowing better mechanical leverage, therefore more force applied with same force required.

2) Different type of spring with better curve to apply force.


Also, I assume I could order this unit and have my local BMW dealer install it, and my tech would not experience hardly any difference in the install process compared to the factory unit?
Correct - the clutch installs even more simply as there is no SAC to unlock (as required with an OEM clutch install), the procedure is exactly the same in every other respect. As long as the tech can follow the simple instructions printed right on the clutch disk of "FLYWHEEL SIDE", there should be no problem.

The big breakthrough with this clutch setup (besides the direct-fit pressure plate) is the clearance in the center of the clutch disk to clear the raised ring in the center of the M5's original flywheel. For those that have been following options along for a couple of years now, that's been the problem with adapting the Sachs Race Clutch designed for the M3, no clearance for that raised ring. The UUC Direct Fit clutch disk clears the ring without any problems.

- Rob
 

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gsfent said:
Rob
Can we then be assured that if we go this route and do NOT use a lightened flywheel there will be NO rollover noise, just like stock??
Thanks.
Regards,
Jerry
Yes, you can be assured.

As far as the clutch assembly is concerned, there will be absolutely no difference in noise compared to before the installation - just like stock when using the OE flywheel.

- Rob
 

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Rob,

One last question...I know this is a bit of a guess, but from your experience, will I likely need a new flywheel given the following:
  • I have a factory original clutch with 26k miles.
  • I have no significant slippage at the current time.
  • The clutch is "soft" on hard shifts. For example, it is to the point that on a fast 1-2 shift, the tires won't even chirp. The clutch hooks up, just "softly" (i.e. meaning there must be some slip but nothing significant that you can feel/hear/see on the tach).
  • The 2-3, 3-4 shifts are also "soft" when done quickly...feels yucky.
  • As best as I can recall, I have never let it slip any significant amount with major power going through it.

My thoughts are that I'm probably ok with the stock flywheel, but will I need to have it refaced anyway to mate well with the new disc? Should I just have them put in a new one anyway since I'm hoping to get a long service life from the new clutch? As you can tell, I don't put that many miles on the car (around 6-7k per year).

Thanks,
Chuck
 

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CSBM5 said:
My thoughts are that I'm probably ok with the stock flywheel, but will I need to have it refaced anyway to mate well with the new disc? Should I just have them put in a new one anyway since I'm hoping to get a long service life from the new clutch? As you can tell, I don't put that many miles on the car (around 6-7k per year).
As for the slow engagement, have you removed the CDV?
http://www.uucmotorwerks.com/html_techtip/techtips/check_valve.htm

At 26K miles, your original flywheel should still be fine.

You don't need to have it refaced. All you really should do is have the tech buff up the surface with a rotary buffing tool, this removes whatever deposits there may be from the original clutch without the expense (and risk) of a lathe-style refacing.

- Rob
 

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Rob,

Can you comment on the Spec Stage I clutch as compared to this new clutch? It seems a few owner opted for the Spec Stage I as an alternative to the 850CSi upgrade as an OEM like solution.

My clutch seems pretty good at 43k miles, but with my learning to drive on the M5, I'd imagine it will go soon. My plan is to get the dealer to replace it under warranty, but have them cover labor, and I'll provide my own clutch. If it happened sometime between now, and say, 60k miles, do you think I'd need to put on a new flywheel?

With this new solution, is it recommended to stick with the OEM flywheel, or is there an aftermarket one that is a good fit that has benefits, but no real downsides?
 
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