Randall Young wrote:
>
> > after alignment today (since it was drifting slowly when i let go
> > of wheel)
>
> Larry, unless you somehow found a road that is perfectly level (salt lake
> perhaps ?), a slow drift to one side is perfectly normal.
>
> > the car still does the exact same thing. i got a computer printout of
> > before and after settings. the mechanic wrote that there is no camber or
> > caster adjustment on the front end. of course these items are
> > out of spec.
> > does this sound right ? if so, how do you fix something like
> > this ?
>
> My TR7 Haynes doesn't show any adjustments per se. However, it does quote a
> fairly wide range (+/- 1 degree) for both caster and camber, so if your car
> is really out of spec, there is likely something wrong. Most likely would
> be worn bushings, followed by accident damage. Or if the camber is high on
> one side and low on the other, possibly a subframe that is out of place. I
> see what looks like a track, or radius rod in the photos; changing the
> effective length by adding shims would change the caster.
I will offer this little bit of antiquity on the subject. In the early
`80s, when I was working in a Toyota garage, we received a service
bulletin which outlined a persistent problem with larger US-spec cars
darting or drifting off the right side of the road. It turned out that
the computer alignment system at the factory had been programmed only
for Japan-spec cars, which, of course, were right-hand drive. The system
was designed to put an additional amount of positive caster on the wheel
furthest from the road crown, and that meant, on right-hand drive cars,
the left wheel, and less caster on the right wheel. That meant that the
car's caster was biased to the right, which made it all the more likely
to go right on a US road which, in left-hand drive, is crowned to the
right.
The correction was quite simple--reverse caster settings from
right-to-left and left-to-right. It might be that you need to have the
car aligned to apply slightly more positive caster to the right-hand
wheel and slightly less to the left-hand wheel. As Randall mentions
above, worn bushings could result in a caster change, as can the
subframe shifting (although I think the latter less likely). At any
rate, check the bushings (and the subframe mounts, if nothing shows up
in the bushing condition of control arms), and if all seems kosher, have
an alignment shop bias positive caster in favor of the right-hand wheel,
which should tend to maintain straight-up and ahead wheel position on
the wheel with greatest tendency to be influenced by road crown.
Cheers.
--
Michael D. Porter
Roswell, NM (yes, _that_ Roswell)
[mailto:mporter@zianet.com]
Don't let people drive you crazy when you know it's within walking
distance.
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