Re: M3 Rotor Warp

[JDJO@xxxxxxxxxx]

Matt Dull had a common M3 track experience:

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My problem which I am sure is common was severe rotor warp. Aside from
spending big bucks on some Alcon setup, can any of you offer some advice
on how to eliminate this problem in the future.  The pads I ran were the
Hawk HP which were fade free and did not eat rotors like the blues.  I
am leaning towards having a set of rotors for the track, and another set
for the street.
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I had my stock rotors warp as well.  AFIAK, the solution is not two sets of
rotors, as you would just warp your track set, and have to replace them
anyway.

The solution:
1a - Buy cheap rotors, and throw them away when they warp - This is
the racer approach, which I find a bit pricey for me.
1b - Buy Euro rotors, which are two piece, and resist warping - These
cost more, but I have not yet had mine warp.  FWIW, these are not
kosher for SCCA Street Prepared, though I doubt anyone would catch
it.

The deciding factor between 1a and 1b may be whether you consistantly
wear out your rotors before you warp them, in which case you might as
well buy cheaper ones.

2a - Bend back your brake rotor backing plates - The price is right, but
this may contribute to road crud getting funneled into your brake/bearing
areas, and that isn't so good.
2b - Brake ducting - The existing duct setup blows nice cool air into the
wheel wells, and some of it might even hit your rotors.  A trick brake ducting
setup will direct the air to the center of the rotor through the back of the
backing plate, and then the air goes through the rotor and out the edges.
Turner sells a kit, and JT Designs is developing a very trick kit as well.
Expect to spend >$500 for both a kit and new bearings to put it in.  I'm
not sure, but Duane or Ron S. may have developed a UUC kit for this
purpose as well.

It's kind of funny.  I don't remember having to do stuff like this to my
Nissan Altima :-)

Good luck,

John
98 ///M3-4 "Calypso" - Euro rotors, awaiting ducting kit

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