At 08:01 PM 1/4/99 -0800, Lawrie Alexander wrote:
>....
>.... I was just trying to make the point .... that if our cars were
designed in such a manner that moving a battery from a position low and in
front of the rear axle to a bit further back in the trunk (where it would
also be higher), then the effects of filling an empty gas tank would have a
disproportionately dangerous effect on the car's handling. And, heaven
forbid, what if you actually put luggage in the trunk and on the
trunk-mounted luggage rack and set off on a trip with a full tank?
Suddenly, a car so sensitive to a battery's placement would become
undriveable!
>....
The reason that shuffling weight around in a production car doesn't affect
handling too dramatically is because almost all production cars have a
substantial amount of understeer built in from the factory. They are built
that way as a matter of general safety on the road, so they're easy to
drive without having to be concerned with the dramatics of oversteer in odd
situations. With a car built this way, when you move some weight around it
just goes from some amount of understeer to some other amount of
understeer, could be more or less, but still understeer.
For those of us bent on achieving agressive handling characteristics, the
story is quite different. Once you get it set up to have near neutral
steering characteristics, some small to moderate amount of weight
redistribution can move it into either understeer or oversteer character.
The former is closer to factory handling characteristics. The latter can
be dangerous if you're not expecting it, or if you're not experienced with
driving a car with oversteer. And yes, a few gallons of gas can do it.
So, for those of you tinkering with your suspension, if the primary end use
will be street driving, you should be quite happy keeping a little
understeer. If you push the suspension tuning to the limits, it will
likely be dramatically twitchy on the road under some conditions, and not
always predictable.
Another $.02,
Barney
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