RE: <E36> Clutch replacement

[Thi VanAusdal <tvanausdal@xxxxxxxxxxxxx>]

> I am experiencing some clutch slipping on my 325i. During normal
> driving at any speed, it drives and accelerates just fine. But when I
> try to launch my car from stop at anything over 3000rpm the clutch
> starts to slip until it eventually catches up. My question is:
> 1. Is this a sign of a worn clutch?
> 2. If it is, what part of the clutch needs to be replaced?
> 3. What is a good aftermarket clutch upgrade for a I6 e36
> 4. How about upgrading using clutch parts form a M3?
> 
> TIA,
> 
> Joe.
> '93 325i
> Doing 0 to 60 in 20 sec... 
> 

Joe,
 Yes, this is indicative of a worn clutch.  The disk is worn to a point
that the clamping force of the clutch plate on the disk is overcome by
the torque of the motor.  Higher-rpm launches will exacerbate, or even
make worse [a Dave Barry-ism] this situation because:
 a: higher rpm ~=more torque than just off-idle (more torque, obviously,
at
3000 than 1500 rpm on your BMW motor)
 b: sliding friction is less than static friction, plus 
 c: you're not off the clutch 100% as you launch, reducing clamping
force,
hence more slip.

 STOP doing hard launches like this.  ANY time you slip the clutch from
here on out will accelerate the wear and hence the amount of slippage.
I assume you knew this, though.

 It is ALSO indicative of contaminant on your clutch disk friction
surface
or glazing.  A rear main crankshaft oil seal leak can get motor oil on
the
flywheel and clutch.  Doh.

 Have you had similar problems with prior cars?  If you're hard
on clutches, it's your driving style.  You may tend to slip your clutch
more than the average.   Especially since you're launching at 3000+ rpm.
:)

 I cannot speak for M3 or other clutch upgrades.  I hear people with
100K
on their clutches.  I'm amazed - my '68 2002 went through 2 clutches in
3 years.  Oh, wait, I was 17.  Never mind, driver fixed input problem
(left
leg). :)

 - Thi VanAusdal

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