>From Joe:
>Ah, but even with no feet on brakes... the steering/BRAKING
POWER
>combination in a front driver helps it all happen. In a rear
driver, that
>dynamic is missing.
Nope. The engine braking effect will increase front tire loading
(and therefore grip), REGARDLESS of which wheels are transmitting
the engine braking. Do the statics. The result is the same: a
moment about the tire contact patch is resisted by the front
tires, increasing their grip. In the FWD case, any available
traction that is used for engine braking is NOT available for
lateral grip, whereas this admittedly small self-protecting
limitation is not present in a RWD car.
>> Coincidentally, most current small sedans happen to be FWD,
but the RWD
>> ones turn out to be every bit as rollable.
>
>I've seen no evidence to support that.
>In fact, the evidence I've seen is to the contary.
I'm basing my position on rollovers nationwide over the last six
years of which I'm aware, including more than one where I was
present at the event. My direct experience - two RWD rollos, two
FWD (one of which was mine) - isn't statistically valid, so I'm
not using that as the basis for my argument.
Given that there are very few RWD sports sedans in the
size/weight range that is popular for autox, and that one of the
most autocrossable examples - the E30 BMW 318i - is an
incorrigible two-wheeler and has a documented tendency to turn
over - I have to say the available evidence does not support your
contention.
Any small sedan with high CG is a candidate for rollover in
Stock-legal form with sticky tires. I'd really be interested in
knowing the specific RWD sedans you feel are NOT likely to roll
under autox conditions.
Jay
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