Here's some ideas I've come up with, open for discussion and constructive
criticism:
1) get rid of as much initial slop in the system as possible
2) raise the brake pedal to give it more travel; may not be good for "heel
and toeing", nor viable if you have to raise your leg too far to get up on
the brake pedal; in my case, the steering wheel is somewhat restrictive;
also tends to increase "reaction time"
3) limit the travel of each master cylinder individually by placing a short
1/2" dia rod inside the cylinder [scalloped as required to not block any
ports]; m/c's for drum brakes could probably be restricted more than those
for disks; there is probably way more available travel than normally
necessary, and you should be able "to gain it back" if necessary by pumping
it in an emergency (assuming the brain's in the correct gear)
4) increase each m/c one size, perhaps in conjunction with #3 (but increases
necessary pedal force)
5) weld/bolt a bar to the brake pedal with some sort of stop screws/blocks
to limit how far the bias bar can move; this must be carefully done on an
individual car basis; particularly if the wheel cylinders are vastly
different in diameter (as in my disk/drum setup), one must be careful not to
bottom out the stops in normal operation (and normal operation has to take
into account wear of drum shoes (disk cylinders being self adjusting [we
hope]), and all the thermal changes that take effect between the home garage
and full race conditions
My current thinking is that a combination of small amounts of several or all
of the above may be required.
Thanks,
Dick Tillinger
-----Original Message-----
From: Tillinger, Richard (OLN)
[mailto:Richard_Tillinger@dresser-rand.com]
Sent: October 07, 2002 11:37 AM
To: 'Vintage Race Newsletter (E-mail)'
Subject: almost total brake failure
Hi all,
Just returned from the great SVRA Summit Point event. During the qualifying
race, I experienced an almost total brake failure when all the rear brake
fluid decided it "wanted some fresh air" and went outside. Bad enough, but I
have a dual master cylinder setup, and the fronts should have given me "some
comfort". They didn't because the brake bias bar went over too far, and the
pedal basically made it to the floor. It seems that the fix would be some
sort of limiting stops on the brake bias bar. I don't want to reinvent the
wheel here, and someone else must have experienced this problem and figured
out how to fix it.
Thanks for any advice,
Dick Tillinger
ex-Bob Sharp 2 liter Datsun Roadster (still in one piece, same size as
before, thank goodness ...)
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