Quite some time ago, I used to autocross my street car, a 1980 Buick Regal
Limited. It was a plush car with a little 265 cubic inch V8. It was
severely top heavy and initially would roll onto the sidewalls quite
readily, even with AutoX tire pressures above 50psi.
Although I did not add much CAMBER to the OEM alignment specs, maybe an
extra 1/2 degree, I ended up running the car with 11 degrees of CASTER.
This allowed the front wheels to really "lean into" the turns, keeping the
tread much flatter, without influencing street driving significantly.
Remember though, this car had power steering and it didn't "feel" much
different at the steering wheel. Yes, even with GM's police pursuit
suspension pieces, Moog progressive rear coil springs and KYB shocks, she
still wallowed somewhat, but we almost always finished in the top third of
our class (big 'merican cars and small imports together), much to the
dismay of the smaller, sportier cars who were frequently left scratching
their heads, wondering. ;-)
Later,
Jack (looking for some caster on my TR3) Brooks
1960 TR3A
1980 TR8
1974 Norton 850 Commando
Hillsdale, NJ
> -----Original Message-----
> From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net]On
> Behalf Of RIVERSIDE
> Sent: Monday, August 14, 2000 10:43 PM
> To: fot@autox.team.net
> Subject: caster
>
>
> I will give my 2 cents on this topic even tho I have not yet driven a
> big TR with the 5 degrees of + caster I like. My 4A will get there.
>
> The obvious benefit of better straight line stability is not as useful
> to high performance driving as the benefit to camber gain. You can get
> the cornering camber you want partially thru upper arm angle, tho this
> gets the front suspension acting more like a swing axle than we
> would like,
> partially thru static camber angle, tho this can be detrimental
> to tire grip
> under hard brakeng. Caster, on the other hand, has only
> increased steering
> effort as a bad side effect. BMW has used lots of caster in its power
> steering equipped sedans to minimize camber loss in roll. We did some
> set up work on an old studebaker based sports racer a few years ago.
> One of the things that is hard to do on their old kingpin setup
> is get caster
> adjustment, so we put wedges under the rear of the lower
> control arm shaft
> and raked the whole business back. We found that at about 5degrees of
> + caster, we no longer had a camber loss as the suspension went thru its
> bump travel and steering movement. On the test track the road feel was
> much improved and as cornering loads increased, so did the
> steering effort.
> It never got oppressive, but it was there.
> Bill Boemler told me that he put together a setup for his
> TR3 racer that
> had about 12 degrees of + caster. When I asked him how it worked, he
> replied, "It went around corners better than it ever had and
> after eight laps,
> my arms fell off!"
> art de armond
>
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