John;
Re #4: Another overlooked source of wheel drag is the front wheel
bearings. Tapered roller bearings can be adjusted just to the point of
removing all the play but not putting on a heavy preload. We used to put
the car up on jackstands and then give the wheels a spin by hand and
tighten the adjustment until we could feel a perceptible slowing of the
rotation and then back off a small fraction of a turn.
Re #5: When those rear brakes lock up the wheels, they no longer keep
things going straight.
Regards, Neil Tucson, AZ
-----Original Message-----
From: owner-land-speed@autox.team.net
[mailto:owner-land-speed@autox.team.net] On Behalf Of John Beckett
Sent: Monday, June 28, 2004 1:37 PM
To: Land Speed List
Subject: LSR Brakes - 3rd. try, part 2
4) Disc Brake Drag - If everything is correct disc brakes don't drag. A
square
seal is used on the piston, so that when you take pressure off the
piston the
seal pulls the piston back .001 to .002 which is all you need. Have set
several records over the past fifteen years and disc brakes have never
hindered my speeds.
5) Rear Brakes Only - Applying rear brakes helps keep the car in a
straight
line, much like the rudder helps a plane fly in straight line. Only
problem
with this system is you have lost 75% of your braking. Not acceptable
for
speedy cars at Maxton. Probably impossible for any vehicle at Texas. Now
if
you go too far at El-Mirage or Bonneville you're in big trouble too.
Just
don't see why anyone would still build a car like this.
6) Front Brakes Only - Hate to admit that I've done this. (Stopped from
240
MPH, broken rotor on the rear, 'chute didn't deploy.long story). However
it
does work, but you need to be very careful here too. It's not inherently
stable, although my car was OK, and will overwork the front brakes
quickly,
unless they are greatly over sized.
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