Re: UFO brakes

["Dave Puterbaugh" <deputer@email.msn.com>]

I found the same numbers when I checked my UFO rotors.  I also changed all
the control arm bushings and noticed a very slight change.  I would agree
that the uneven braking surface ( caused by ???? ) is responsible for the
shaking, and it may be more pronounced with the way the rotor is located so
far in from the hub.

Dave Puterbaugh
1991 200 tq sedan
-----Original Message-----
From: Wolff <quattro200@earthlink.net>
To: FBFISH@aol.com <FBFISH@aol.com>
Cc: quattro@coimbra.ans.net <quattro@coimbra.ans.net>
Date: Sunday, March 14, 1999 9:39 PM
Subject: Re: UFO brakes


>FBFISH@aol.com wrote:
>>
>> In a message dated 3/12/99 3:26:36 PM Eastern Standard Time, quk@isham-
>> research.demon.co.uk writes:
>>
>> << I disagree.  They're sound engineering and provide the sort of
stopping
>>  power that a car of that size really needs if it's going to be driven
>>  by anyone other than an undertaker's chauffeur.
>>   >>
>>  Well said Phil, I have over 120 Kmiles on mine and never had a problem.
I am
>> curious about all the warping one reads about on the list. Does anyone
have an
>> "engineering" explanation?
>> Frank Santoro
>> 1990 V8
>> 1998 A8
>
>I can say for sure that although my UFO's pulsated noticeably, they were
>not "warped". The runout was about .001" (yes, only one 1000th). The
>hubs just for comparison were about .005" out and that's at a much
>smaller radius too. The rotors were turned and the pulsation was cured
>without doing anything to the hubs. (Prior to turning the rotors, the
>front wheel bearings and all subframe bushings were replaced with no
>noticeable effect on the shimmy. ) I think that the pulsation is due to
>an uneveness in the friction surface of the rotor. One portion is
>grabbier than another.  I have no idea what causes this. It also could
>be that some rotors warp and others like mine were, are uneven. Has
>anyone else measured the runout (off the car) of their "warped" UFO's?
>Wolff
>