[s-cars] Rotor hats and rings

[Eric Phillips]

On 4/11/06, Taka Mizutani <t44tqtro at gmail.com> wrote:
> Eric-
> Losing weight at the rotor hat is not going to significantly affect thermal
> mass, so
> if you can afford the $$$, I'd say go for the 2-piece rotors, fixed hat,
> with directional
> vanes, no cross-drilling, if possible.

http://www.bira.org/info_main.html

Just as a basis for comparison, the Coleman Repli-Rotors are half the
mass of stock Audi rotors.

Thermal mass is thermal mass - conduction means that the hat is as
much in play as the rotor surface itself.

The rest of your statement is 100% percent true.

> AFAIK, Igor is not tracking the S6, so this warping issue is from street
> driving. That said,
> I wonder what kind of driving he's doing to warp rotors on the street. I
> never had any issues
> with similar boat-anchor MBZ rotors, but maybe the directional and
> differentially vaned
> MBZ rotors either have better metallurgy (these were OEM MBZ with MBZ labels
> and part
> numbers) or better cooling or both.

Even my crappy VW rotors got the holy living crap flogged out of them
on the street (when I was young and dumb[er]) and never warped.  Talk
about tiny disks...

> I've had no warping issues with boat-anchor STi rotors either, similar size
> (326x30mm).


He did say they were a bad casting batch. I'm not too worried about
the warping aspect -  I'm more worried about the adverse handling
effects of the larger unsprung mass.  I guess I'm going to find out,
hmmm?

:)


--
Eric

1995 UrS6 "Silber Geist"