> Ive noticed that on our VR4, the front brakes get hot as hell
> (of course) but the rear brakes just never get very warm..at all.
>
> Will barely steam when applied with water after a run, sometimes I can
> almost grab the rotor.
First of all, quit running water onto your brakes before you warp the
rotors.
(Second of all, quit putting on your parking brake after a hot run, before
you warp the rotors.)
Third of all, as Phil said, your front brakes are going to be doing most of
the work in any case, and this only increases with sticky tires. They allow
the chassis to transfer more weight forward before they start to slide.
If you have too much front brake bias (fronts lock before rears), then yes,
you want to increase the rear brake bias. I've noticed this to be more and
more true on many cars newer than about 1991 (ever drive a Viper?!). You
should be able to tell even with ABS whether the front or the rear goes into
ABS first. While ABS keeps the bias from being as serious an issue as it is
with non-ABS cars (ever drive a Viper?!), bad bias is still undesirable,
because you don't usually want to stamp harder on the brakes once the fronts
are into ABS to get the rears working fully. (See sure-to-follow
long-winded thread about ABS.)
If this is your situation, then yes, running a more aggressive pad on the
rear axle is a stock-legal way of changing the bias to be more rearward.
You do need to be aware that different pads heat up at different rates, and
work differently at different temperatures. That makes this technique often
practically useless on non-ABS cars, because you end up with a car with
changing bias as the brakes heat and cool. However, ABS will help to
average everything out, and in any case you won't be much if any worse off
that you were with the original problem.
Note that you don't necessarily want the latest ceramic-kevlar dual-bonded
work-on-the-surface-of-the-sun race pads. We've already determined you
aren't getting enough heat out of the rear brakes, and with full-bore race
pads you may not be able to get them hot enough to start working. A more
aggressive street pad is more likely to work well enough cold to brake more
effectively without overheating.
KeS
(has driven a Viper. Not sure how we eventually got stopped, but it wasn't
pretty.)
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