[s-cars] Understeer vs. oversteer?

[serge]

Joey, Joey, Joey

Think of it in terms of compliance (soft, rubbery, gooey) vs. resistance
(stiff, like stone). Those stiff springs don't give you traction (not
directly), the tires (soft, rubbery, sticky‹compliant) do that. Making
things stiffer allows you to keep suspension geometry more consistent as you
flog that car through turns (transferring weight from back to front, side to
side....) Adding sway bars (the correct term is anti-roll bars), further
reduces body roll, and gives you that lovely flat-cornering feel.

However all this joy comes at a price. Remember, compliance=traction. By
making things stiffer, you have reduced your compliance. You have reduced
your traction at the limit (though you may have raised that limit overall).
You have increased your ability to carry more load/speed (stiffer springs)
through the corner and flattened out some body roll (bigger sway bar), but
once you have exceeded available traction (tires) that baby's gonna break
loose, and quickly.

To put it simply:
Increasing the stiffness (reducing compliance) of the front end, will lead
to more understeer (front breaks loose first). Adding stiffness to the rear
will lead to more oversteer (rear breaks loose first). Playing around with
both to suit your driving style will result in a happier driver.

This is all a major simplification of chassis dynamics on which I am no
expert. It assumes perfectly smooth pavement, and does not address the
function of shocks, tire pressures, alignment, sprung/unsprung weight,
torsen funk..... Anyone willing to shoot holes in my oversimplified
statement is welcome to do so. Our 4000lb cars can use very high spring
rates, and would probably benefit from massive sway bars, along with solid
suspension links and engine/trnsmission mounts. But that would make the car
lousy for ANY kind of street driving, and we would all be back to that "our
cars make lousy track cars because they are so heavy" thing.

HTH
Serge

> List,
> Our cars understeer like pigs (not unlike my date this
> weekend) because all the weight's on the nose, right?
> Understeer is caused by front wheels losing traction
> before the rear, so the car plows.  Adding a Rear Sway
> Bar should increase the rear traction.  Hap, wouldn't
> this make understeer worse?
>
> Joe, confused as hell in NY, Pizzo
>
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