> With stock calipers they say it takes 262 feet to stop from what I am
> assuming is 60mph. WHAT??????????????????????
I have always been deeply suspicious of John's figures ... no idea why his
car wouldn't stop but there was clearly something wrong, IMO.
Unless you suffer from premature rear lockup, or cannot lock the brakes at
all, the Toyota 4-pot conversion by itself can only increase your stopping
distance, because it moves the brake bias heavily to the front. On my TR3A
with stock brakes (but upgraded tires and wheels), I have no trouble locking
up the front wheels when necessary, while the rears only lock well after the
fronts. And I've learned the hard way that it will out-brake most cars on
the road !
> How can this be? I checked the numbers in the latest issue of C&D and they
> show any of the jumbo SUVs and 4x4 full size crew cab Pick ups capable of
> stopping well under 200 feet from 70mph. Am I missing something here? How
> can it be? I was planning on doing some major brake revisions to make it
> stop on a dime. Is it the tires or the rear drums or what?
Tires could certainly be a problem, it's impossible to buy high performance
tires in the original sizes. Rear drums are not a problem in these kind of
tests ... their limitation is that they don't cool as well as discs, but
unless you get them hot enough to suffer brake fade (further increasing the
front bias), they work just fine.
ABS may be another big difference, it certainly reduces the variance due to
driver skill. I have seen tests where a skilled driver, under ideal
circumstances, can out-perform ABS; but most people cannot. And of course
ABS solves any bias problems under the prevailing conditions, which is
impossible with fixed bias systems like the TRs.
> While I'm on it, does anyone have any old road tests on TR's in old mags
> like R&T or C&D?
Thought I had some for the TR3A, but can't lay my hands on them at the
moment. However, a Sports Car Graphic road test for the Stag, published in
June 1971, reported a stopping distance of 150 ft from 60 mph. They also
checked for brake fade, said it was "unattainable". Since the Stag's brakes
are fairly similar to the TR6, I would expect similar performance.
> I'm curious as to how they and other cars of the time may
> have performed as well. Think I will have to hit a few of the auto swap
> meets and pick up some old mags when I get a chance.
FWIW, Brooklands also publishes collections of articles from old car mags
about a specific model.
Randall
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