BMW M5 Forum and M6 Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
682 Posts
Discussion Starter #1
I am looking to get a better clutch for my M5 and was wondering what my options are other then the $3000 UUC unit. My car is strictly a street car and will see no track time. I would love to be able to leave from a dead start with a little more umph if possible. I was wondering what you guys would suggest?

Also am ready to do a suspension upgrade but mainly to lower the car, again I don't track my car and I don't need adjustability so coilovers aren't neccessary but i'm not completely opposed to them. I was thinking of the Bilstein PSS9 if I do go with the coilovers. What is available in a straight spring and shock setup? I don't want to sacrifice my stock ride entirely so anything to stiff need not to be suggested.

Help me out guys with suggestions and where to find the parts your mentioning at the best prices?
 

·
Registered
Joined
·
2,289 Posts
mady...

i would say to look into the 9 1/2" spec unit then..if i remember marcvip's 24page rant, it was less expensive than the UUC. Although i do not remember 100%.

As for lowering..as someone that is kinda pissed that i lowered my M (3) with just springs and how poorly it rides, i would suggest that you look into a lower cost Ground Control system.
 

·
Registered
Joined
·
1,472 Posts
H&R front springs only. Nice lowered front (even with rear) giving it an aggressive look without the hassle of adjustability.
 

·
Banned
Joined
·
300 Posts
I had installed the adjustable Bilstein PSS9 coilover kit on my last BMW and I highly recommend it......very comfortable ride yet lowered as much as you want...
 

·
Registered
Joined
·
1,345 Posts
I have the Eibach heighta djustable set up and it sits 40mm lower front and rear with NO bottoming or spoiler problems in car parks etc. The most recent piccies are here !


http://www.m5board.com/vbulletin/showthread.php?t=53402

I would go for the PSS9.... It wasn't available when I bought the Eibach, I have never done a back to back, but Billies are Billies.......:haha:
 
B

·
Guest
Joined
·
0 Posts
Do the following (available from BeastPower) and you will be a very happy camper:

- KW Coilover Suspension (variant 2).
- SPEC Clutch (lightened - stage 3).
- SPEC Lightweight Flywheel.

Cheers, Daniel.
 

·
Registered
Joined
·
176 Posts
BeastPower said:
Do the following (available from BeastPower) and you will be a very happy camper:

- KW Coilover Suspension (variant 2).
- SPEC Clutch (lightened - stage 3).
- SPEC Lightweight Flywheel.

Cheers, Daniel.
I installed the SPEC stage 3 and lightweight flywheel mid-march. 3,000 miles later and I am putting in another flywheel and clutch....one side of the disk was fried. Put 780 break-in miles on the clutch before hammering it.

The "hybrid" clutch disk may not be a good idea, as the side with the Kevlar looks like it grabs and causes the ceramic side to slip. The side with the lower coefficient of friction was down to the rivets, while the kevlar pucks looked near-new.

* Note: It may not be a function of the mixed materials, as the clutch assembly could be defective. Unlike most cars with clutches that are toast, the clutch pickup was not at the end of the pedal travel, but 1 inch off the *floor*..it was near-impossible to get the car in and out of gear because the clutch was not disengaging completely.... Confused myself as well as the tech. Hydraulics were checked and found to be working 100%

Jury is out with me. I am hoping to get it replaced with a clutch stage that does not have mixed materials. SPEC RMA'd it and will be receiving it later this week.

FYI.
 

·
Registered
Joined
·
1,037 Posts
not all coilovers can be lowered and maintain suspension travel -- the GC coilovers really need to be run near stock ride height to maintain suspension travel in front (rear not a problem) -- could probably lower up to an inch below stock if the bump-stops are cut but i'm not sure how much safety magin this leaves

re clutch -- kevlar is not recommended for normal street use and UUC no longer recommends it for the M5 at all -- kevlar does not hold up at all to drag-racing starts and UUC now says that the M5 is too heavy and powerful for kevlar period (i have a early UUC with kevlar that they recommended for track use - so far it seems to be okay) -- the idea of a combination of kevlar and ceramic sounds completely stupid
 

·
Registered
Joined
·
4,515 Posts
Bugeater said:
I installed the SPEC stage 3 and lightweight flywheel mid-march. 3,000 miles later and I am putting in another flywheel and clutch....one side of the disk was fried. Put 780 break-in miles on the clutch before hammering it.

The "hybrid" clutch disk may not be a good idea, as the side with the Kevlar looks like it grabs and causes the ceramic side to slip. The side with the lower coefficient of friction was down to the rivets, while the kevlar pucks looked near-new.

* Note: It may not be a function of the mixed materials, as the clutch assembly could be defective. Unlike most cars with clutches that are toast, the clutch pickup was not at the end of the pedal travel, but 1 inch off the *floor*..it was near-impossible to get the car in and out of gear because the clutch was not disengaging completely.... Confused myself as well as the tech. Hydraulics were checked and found to be working 100%

Jury is out with me. I am hoping to get it replaced with a clutch stage that does not have mixed materials. SPEC RMA'd it and will be receiving it later this week.

FYI.
You followed proper break-in procedure, unlike some folks who experienced failures of abused aftermarket clutches. I would agree the 9-5/8" Kevlar/ceramic unit is a loser.

With respect to your other issue.....

Incomplete disengagement with Spec's 9-5/8" Stage 3 disk was reported by another owner here. In their case, Spec attributed it to the owner reusing a dual mass flywheel (in decent condition) without refacing it. They claimed that a new flywheel or resurfacing is mandatory. Spec added that non-refaced flywheels are typically warped and will cause this symptom. Being familiar with the common practice of reusing unscored flywheels without resurfacing, I questioned that scenerio. It now seems there is an incompatibility between their disk and the pressure plate travel at full pedal. Clearances and/or tolerances are marginal. The new Spec disk is either too thick or the pressure plate travel is too short. A larger bore slave cylinder may be a bandaid fix, but it's hard to predict the outcome...aside from increased pedal effort. Under this Spec clutch scenerio, it's a race between clutch break-in and tranny synchro wear-out or warpage. The pressure plate travel may be maxed out with the stock cylinder. I don't like the odds....sounds like a design issue.

The clutch failure is likely unrelated to the clutch-dragging symptoms.
 

·
Registered
Joined
·
176 Posts
Interesting post lscman. In my case as I believe you summised I used all new components. I have since the original post received a new aluminum flywheel from Rogue and will be calling SPEC monday to see about the RMA status of the clutch assembly. I hope to convince them to allow me to get a mono-material clutch whether it be organic, kevlar or cottage cheese...I dont care if its grabby. I am used to that with the 7.25" tilton clutch in my racecar, and it would deter my wife from wanting to drive it ;)

Christ maybe I should put a tilton in it. That thing holds 600ft/lbs of torque with no problem, all day long, and costs (gasp) 350 bucks to replace.
 
1 - 11 of 11 Posts
Top