Re: Brakes in General

[STEADIRIC@aol.com]

>OK, so fade is due mostly to heat then, right?  And this increased heat is 
>what melts the pads right?  Possibly warping the rotors?  Can heat 
>cause brake fluidin the calipers to boil, and screw up all sorts of things
too?
>(Or is DOT 4 fluid supposed to prevent this...)  
Yep! Heat = Fade = pad melt (Actually the vaporization of the binder 
material which helps in the fade process) = rotor warp = fluid boil.  Dot 
4 helps but Hi-temp Race fluid is better..... ONLY If you change your 
fluid regiously!  It can absorb water.

>Also, what's the advantage of the dual
>piston calipers I've got on there?  Heat dissipation, or clamping power
>(possibly both?)  I'm assuming vents to the front brakes wouldn't be a bad
>idea?  There's enough vents under that bumper, something should work.  If
all
>else fails, who needs those pesky front turn signals anyways, right?  
>(besides, a little creative engineering would relocate them to the
>useless parking lights in the turbo lenses anyhow...)  
More even clamping pressure to help reduce taper wear making your pads 
more efficient. Yes more air in there would help.  Your looking in the 
wrong location though....
 
>Also, rim design.  I know rims help brake
>cooling if designed right, and aluminum is the best way to acheive this.  Is
>this because they're (the rims) designed to pull air over the brakes when
the
>wheels are spinning, or because the rims are designed to dissipate heat away
>from the brakes?  Possibly both??  Can the size of the rim help or hurt?  
>I.E.,
>a 16X7.5 rim can dissipate or cool or whatever better than a stock 15X6 can?
>
Hmmmmmmmm........  I've got MSW type 55 wheels with 6 spokes and lot's of 
open space.....

>> Last August
>> at the Blackhawk event I was Working with Brian Collins trying to get him
>> to use his brakes more effectivly.  When we came into the pits after 2
>> cool down laps we shot the Rotors, Calipers, and wheel face with a
>> Optical Pyrometer and got some absoultly terrifing temps.  Rotors Over
>> 880F, Calipers 650F, wheel face 350F.
>
>When Brian was racing at Summit Point this September, he had the same
problem
>(multiplied by a screwed accumulator.)  One of the turns he went into almost
>landed him in the trunk of a 944.  He came in the pits, we jacked up the
car,
>and you could see the cross-drilled holes full of brake pad remnants.  This
>seemed really extreme, none of the other cars had this extent of heat damage
>('course, Brian was hauling around the track faster than most others, but
>still...)  Could this have also had something to do with the fact that his 
>200
>is three inches closer to the ground than it should be?  Complicated by that
>skirt he's got on there blocking air flow to the brakes?
First  The screwed accumulator only means that you have to push harder on 
the pedal.  His other problem is that he goes to Trak-Auto and get's the 
cheapest organic pads that he can get with a lifetime warranty.  He 
usually has fade on the 3rd lap and then just keeps pushing....  Ride 
height has very little to do with fade, and the Skirt actually helps to 
cool the brakes.......


>> So. The Q's are way
>> under-braked IF You are going to take the car on the track or do some
>> spirited street "Touring".  If you ONLY drive on the street you SHOULD be
>> okay.... But the Moment that you upgrade the HP your on the line brake
>> capacity wise.
>>
>SO, since Ned's had his hands in my box and spring perch, you're saying...
>  Umm, OK, I think I get the picture...
See........




Later!

Eric Fletcher
'87 5KCSTQIA2RSR2B

STEADI RIC@aol.com