[Mgs] crossed drilled brake rotors

[Max Heim]

I can't speak for my MGB, but on my other car (which weighs 3400 lbs), I
recently fitted cross-drilled, slotted, vented rotors, replacing the OEM
vented rotors, which were seriously warped (and notorious for doing so). I
then had the opportunity to do some vigorous driving on mountain roads,
including downgrades of 9% and more. One on of these, due to catching up to
slower traffic entering a series of hairpins, I managed to completely fade
the brakes, so that it took several hundred feet to stop on a gravel turnout
with the hand brake full on. After sitting and cooling for 15 minutes, I was
able to continue. The rotors did not warp or show any other sign of damage.
I attribute the fading to the fact I was using OEM organic brake pads rather
than anything more aggressive, and that this car has a non-lockup automatic
transmission.

I suspect that cracking issues arise when people cross-drill their own
rotors without proper stress relief.


-- 
====================
Max
1967 Fastback
Johnny Lightning Muscle Cars USA #14
273 Commando
Factory disc brakes
Mountain View, CA





on 9/20/07 4:53 PM, Eric Erickson at eric at erickson.on.net wrote:

> Running "oversized" tyres that restricted some airflow around the
> brake discs I warped a front disc at the track in a way that scared
> me so much that I didn't want it to happen again.  So I tried the
> cross-drilled/slotted rotors,
> 
> They have been on the car for almost five years now, road and track,
> and have not experienced any negative issues with them.  I can't
> really tell if they have IMPROVED my braking that much - I am just
> happy not to have experienced the bad stuff that I experienced with
> my "standard" discs.
> 
> No noticable "cheese-grater" effect on the pads - I don't go through
> more pads than expected or acceptable.
> No cracks - five years of tough work and they are fine.
> 
> Now all I have to do is remember the brand so I can recommend them :-)
> 
> 
> 
> 
> Eric
> '68MGB MkII
> Adelaide, South Australia