Re: silicone brake fluid - long response. Pass if you choose.

[LtWacko@xxxxxxx]

In a message dated 6/14/2003 3:03:01 PM Central Daylight Time, 
khoi@domain.elided writes:
> 
> Rodney<<
>  
> I do not understand your logic. Your argument above would seem to suggest 
> using Silicone Brake Fluid in a street car. Why is Silicone brake fluid in a 
> street car a very bad idea when it does not absorb water. Am I missing 
> something??
>  
> Khoi 
Since silicon brake fluid cannot absorb moisture in the brake lines, the 
moisture will pool in the lowest part of the system....  THE BOTTOM OF YOUR 
CALIPER!!!  Water is heavier than brake fluid.  It is ever present in your system.  
The bleed screw on the caliper is on TOP of the caliper.  It is on top so when 
you go to bleed AIR out of the system, the air bubbles RISE to the top.  Air 
bubbles tends to do that...  Since the heavier water is pooling in the BOTTOM 
of the caliper, it will cause the piston and other parts of the INSIDE of your 
caliper to RUST either damaging the rubber seal which keeps brake fluid in 
and/or "freezing" the caliper stuck.  You cannot bleed all the water out.  If 
anything, you would have to bleed the brakes more if you use silicon.
 
Let enought water pool in the bottom of your caliper and your braking 
performance worsens fast!  Under spirited driving, the water pooling in the bottom of 
your caliper will boil causing air bubbles.  The bubbles will compress not 
allowing brake pressure to squeeze the calipers.  THE OPPOSITE EFFECT OF WHAT 
YOU WANT!  Great performance, short life.  NOT FOR STREET USE.
 
DOT4 and DOT3 absorbs the "damaging" water.  Eventually the fluid will become 
saturated.  All good things must come to an end.  There is always a 
compromise and price for something.  We pay more for a BMW for a reason.  We pay less 
for a Kia for a reason.  Others pay more for a Porsche for a reason.  More pay 
the same for a Lexus for a reason.
 
Parts for racing aren't necessarily better.  I left my "r" coumpound tires as 
long as I could one fall season.  There wasn't enough tread left for any 
track sessions - just enough though for some "fun" on the street.  When that first 
snow fall hit...  Let's just say it sucks getting stuck in a parking lot that 
had both exits uphill and you are wearing leather bottom shoes!
 
So what is the advantage of Silisone brake fluid?  
    It doesn't compress as much as DOT4/3 giving better brake performance and 
feel.
    Has a higher boiling point.
    Great for RACINGand RACING BUDGETS!!
 
Sorry for the long rant.  Someone please correct me if I am in some way 
wrong.  
 
Rodney
"How do you make a $Million in racing?  First you start with $10 million 
dollars...  "  - Formula 1 Qoute from someone.
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