[s-cars] 117 degrees ambient - Brake issues

[CyberPoet]

Scott,

    117 degrees ambient is around 150 - 170+ degrees at the first 6" -
12" from the black top (think shimmering haze). Is this enough to make
a difference to the pad compound? In a single word: yup.
   If the brakes normally run around 200 - 220 degrees in 85 degree
road-level ambient after usage, then adding in another 60 degrees (and
the resulting lack of heat loss, exasperated by lack of humidity to
carry the heat) will run the pads much hotter (guessing here: 100
degrees over "Colorado" normal over the course of a longer ride?). So
the question then becomes, does a 100 degree difference at the pad face
make a difference to the pad material? Again, yup.
   If it's an organic compound, 100 degree difference is a radical
difference. For sintered pads, it can still be a very big difference,
depending on the bonding agents used in the formulation (for detailed
technical discussions on the different pad formulations, pros and cons,
when to/when not to, see a previous post of mine concerning brake pads
last year in the archives -- search for the words sintered
semi-metallic).
   I'd stop by Performance Automotive (or some similar, if they don't
exist in the Phoenix area any more) and ask at the counter about what
kinds of compounds they are recommending to the gear-heads running
big-block cars from the 70's. Then find a similar compound for yourself.

Cheers
=-= Marc Glasgow
www.cyberpoet.net
Tampa's Leading Apple Macintosh Consultant since 1990


SCOTT WROTE:
Brakes were really squealy in the heat.  Brake dust was almost
"chunky"...
could a few degrees (or 50) make that big of a difference in the pad
compound?  I finally nailed most of the squeal with anti-squeal cheez
whiz
but now I'll try again but go crazy with it on the pad backing...