Big Brakes

[Unka Bart]

Holas, Amigas y Amigos

A minor contribution from DEBUNKMAN (aka, yer kindly ol' Unka Bart) on this
subject.

>-----Original Message-----
>Reply-To: "Alexander van Gerbig" <Audi_80 at msn.com>
>Subject: Re: Big Brakes
>Date: Fri, 31 Aug 2001 03:28:18 -0400
>
>    It's all about locking those tires up.

No offense, Alex ol' Chum, but it ain't about that at all.  It's all about
changing kinetic energy to heat, and bigger brakes are a dandy way to do
that.  Locking those tires up is the worst way to stop that there is,
unless one includes the option of not (seriously) braking at all.

In fact, unless the laws of thermodymanics (like nearly everything else in
the world) have changed dramatically since I studied them at COL Thayer's
Institute for Wayward Youth in my Cow year in 1959; in a moving automoble,
the "braking force" varies as a function of the coefficient of friction
(all other things being equal) between the contact patch of the tire and
the road.  And the simple, if counter intuitive, fact is that the
coefficient of friction between a rolling tire and the pavement is
significantly greater than the coefficient of friction for the same tire,
when sliding.  Optimum breaking is achieved when the tires are *NOT* locked
up, but are on the threshold of being so.

Please note the "all other things being equal" caveat.  A larger contact
patch helps increase braking force  as does a larger heat sink (bigger
brakes) into which to dump additional heat (more thermodymanic engergy
converted from kinetic energy).  Either will improve both stopping time and
distance, both will improve things even more.

Being a (62 year old) newly (34 days) married man means that I don't read
the digests as often or in as much detail as I otter, but this is the first
time I've had a chance to jump in on a thread in quite a while.  And having
a much younger, Red-Headed bride means both that Pharmaceutical sales are
up in direct relation to the decline in my time available for
internet-related (or any other non-spousal) activities.

BTW, she and I hope to see as many of you as we can at the Audi corral at
Road Atlanta for the Petit LeMans in October.  Look for the big ol'
Ex-Grayhound, aka, the dirt-boat "Gatorojo."

Bart