Re: E46: Clutch + Pressure Plate + Flywheel = $1500.00

["Tarun Kundhi" <julie-tarun@xxxxxxxxx>]

> I don't believe my technique is extreme here. That is, I can see how
using a
> lot of slip for a really smooth start (like, 3-5 seconds of slip)
would
> generate quite a bit of heat and wear on the disc, but my approach is
much
> more "friendly," I think. I prefer to get my business done quickly,
without
> a lot of transient loading of the clutch, i.e. my idea of the perfect
launch
> is 1 - 1.5 seconds of slip with absolutely linear acceleration (at the
rear
> wheels) and absolutely no jerk. (For more-aggressive starts, replace
1 - 1.5
> seconds with .5 seconds and leave other factors alone).

Seems resonable.

> This brings up a great point. The double-vanos 328i motor is fairly
torquey
> down low, and there is a zone in all of this clutchwork where I think
the
> driver can get lulled into using the torque as a cRutch. There's a
point in
> the launch, after the initial roll, where you can dump the clutch all
at
> once, yet still achieve a linear acceleration at the rear wheels and
no dip
> in RPM. In other words, this zone is a place where transient loads on
the
> clutch can be quite non-linear, while the load placed on my butt in
the seat
> (apparent acceleration) is very linear.

I assume that this is the procedure that you use for agressive starts.
And you, floor the accelerator.  Have you tired using this method for
the clutch while gently applying the throttle?  As you describe the
torque should enable a smooth start.  You can have a smooth start
without being completely linear on how you let the clutch out.

> So, to pull it all together, your statement about trying to achieve
> smoothness, albeit at the expense of clutch wear, is quite possibly
one of
> the most important things to talk about here, because my definition of
> "abuse" is VERY closely tied to the notion of smoothness. In my world,
> "abuse" equals the "absence of smoothness," but, as you point out,
where the
> clutch is concerned, quite the opposite may in fact be true.

I am not sure that smoothness and abuse are as directly related as
described in your definition.  There are circumstances (outside of this
clutch issue) were being smooth can still be considered abuse.  Maybe
your definition comes from the notion that when people abuse their cars
they are generally not operating them in a smooth manner, therefore when
a car is driven smoothly it is not being abused.

Many people (maybe even a few on this list) feel that taking your BMW to
an autox or driver's school is abuse.  I certain wouldn't agree with
them.  Others may ague that you shouldn't drive them in snow or rain.
BMW are ment to be driven.  Take them to an autox or DS, drive them hard
and enjoy them.  In my opinion that is not abuse, that why the guys in
German designed these cars as they did.  This will however cause
increased wear on components like the clutch, tires and brakes  (engines
and transmission in the long run).  Out of curiosity, is the dealer not
covering the items because they say you abused the car or is it because
the clutch is considered a wear item?

Tarun

ps - praying for spring to come to the Northeast, so I can stop abusing
my M3 by letting it sit idle.

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