Matthew,
>All-
>
>This questions may be too generic to answer definitively
>however that just shows how badly I need opinions.
>
>If I have a car with ABS that cannot be disabled is it
>reasonable for me to assume that the car will stop in
>the shortest distance possible if I simply slam on the
>brakes (thereby engaging ABS)?
Not necessarilly. Engaging ABS in the dry will result in slightly longer
stopping distances than "perfect' non-ABS stops. The basic reason for this
situation is that ABS systems, when they sense (impending) lockup, will
release line preasure for a very short time before allowing the actual
pedal/boost preasure to return to the caliper. During each preasure-release
cycle, stopping efficiency is reduced. Depending on the sophistication of
your system, ABS engagement may have more or less effect on stopping
distances. In wet stops, ABS engagement will come closer to providing good
stops compared to the "perfect" non-ABS stop. Reason being, its really hard
to avoid wheel-lock stops with non-ABS systems in wet conditions. However,
something to remember is that under ABS stopping conditions, You can still
turn the car which, with non-ABS-system heavy breaking, tends to result in
lock-up off-course excursions.
>If this is not so then what sort of penalties are likely
>in this scenario? In other words does a good ABS system
>get within 10-20% of ideal non-assisted braking?
My guess is yes but, that's not good enough if you're really trying to get
maximum performance (lowest times) from your runs.
>How about in the wet (where yesterday I had abysmal braking
>most likely due to driver errors)?
Different tires work differently in the wet and dry. In my case, my "rains"
have great acceleration "hook-up" (even with 300+ RWHP) but only marginal
stopping traction compared to how they work in both dynamic situations
during dry conditions.
>Also if engaging the ABS is evil what techniques can be
>used to avoid the dreaded HAL9000 intervention?
Practice!
Don
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