"rw" > wrote in message
link.net...
> Cory Dunkle wrote:
> >
> > Power assist does nothing to make the car stop more quickly. If you
can't
> > lock the wheels, or the back wheels lock before the front then there is
a
> > problem.
>
> This is puzzling to me. I'm a bicyclist, and I know that on a bike if
> the back wheel locks before the front wheel it's no big deal, but if the
> front wheel locks first, your face will be on the pavement.

Drive the Mustang, or any car without ABS. Get moving well and good, and in
a safe spot decellerate rapidly, then lock the wheels. You will feel
yourself stopping, the g-forces on your body, as the car stops hard. Then
when you lock the wheels you will notice a difference, right when the wheels
lock you feel the car move forward more quickly. That is to say, your rate
of decelleration slows. The limitation of _any_ properly setup brake system
is the tires. A tire has the most traction when it is rolling, and the least
traction when it sliding. Therefore, a sliding tire (locked wheel) will move
faster (decellerate slower) than a non-locked braking wheel.

Think about that for a second. What happens if you front wheels lock first?
Well the car will take longer to stop if you keep the wheels locked. What
about if the back lcoks first? If the back locks first the rear end of the
car will not have the same rate of deceleration as the front, and will be
trying to move faster than the front of the car and have little side to side
traction. The end result is that the rear end of the car will try to move
ahead of the front end of the car, which will manifest itself with the back
end sliding out to one side or the other and putting the car into a skid if
the driver does not know what he/she is doing.

On a bicycle I believe it's worse to lock the front wheel first because you
onyl have to wheels. The front steers and helps keep your stability more
than the rear. If you lose side to side traction on the front wheel it amkes
the bike very unstable and much ahrder to control than when the back wheel
locks.

> I'm definitely getting the dual reservoir master cylinder. Thanks to
> this newsgroup for suggesting that.

Good. I drive a '68 Galaxie 500 (first car was a '67 Galaxie 500, a few
years ago). In '67 Ford made dual reservoir master cylinders on all their
cars standard. My girlfriend wants a '65-'66 Mustang (will be her first
car). A friend from work has one he has had sitting in his garage for
several years he probably sin't going to do anything with. So we may end up
getting that car for her. If that's the case, since it's been sitting for
nearly 10 years one of the things I'm going to do to it is to replace all
teh wheel cylinders and the master cylinder. While I'm replacing the master
cylinder I'll put in a dual reservoir master cylinder and distribution block
from a '67 or later model car. Just one of those things that would probably
never be a problem, but if I'm in there I'm definitely gonna upgrade it
because I don't wanna take any chances with the girl I love over a
relatively cheap and easy conversion.

> Finally, can anyone recommend a good vintage Mustang mechanic in the SF
> Bay Area? I used to be a shade-tree mechanic, years ago, but I don't
> trust myself to work on the brakes of my daughter's car.

Brake work is pretty easy and straightforward, but if you don't trust your
work it's always best to have someone who knows what they are doing do the
work. If you don't know for sure about the carb or something it's no big
deal, the worst that happens is you won't go, but it gets real bad very
quickly when you can't stop! Emergency brakes don't stop cars very quickly
at all. Anyhow, I'm from the east coast, so I can't help you with a good
mechanic.