Just a hunch:
Check the actual OD of the pair of  tires on the drive axle.  This
sounds like a tire mismatch problem which causes the diff to falsely
interpret the speed differential between its two outputs , the left
and right drive axles.  It take as a surprisingly small difference
side to side to broadcast a very uneasy effect.
I had the problem at LeMans in a car we were developing.  It wanted
to track side to side at 230mph under full power using up the entire
width of the Mulsanne.  As soon as you backed off,  the car ran
straight as an arrow.  I handed it over to my co-driver,  Mr.
Expendable.  He retired shortly thereafter.
The problem turned out to be the diff.  It would apply power to one
output and then cycle to the other, slowly, causing the car to steer
from the rear.
Your description reminded me of the whole mystery, and since there
was a recent tire change involved,  I throw it out there.
-Reeves
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I'm betting on the tire solution. I chased this very problem on my  RX7 year
ago. The tires were parked the same, but after pulling them off,  there was
an obvious difference in the two tires. And it wouldn't effect the  steering
wheel. Its just the rear of the car trying to pass the front.
Bob Mears
---------------------------------------------------------------------- --

Also, if they had the tires off during the clutch work, and then put
them back on
different locations may cause it to behave like you described.  Just a
hunch.
Mark S.

-
Got the RX8 back today...problem located, fix is on the way...

And the winner is.....
-Reeves was the first to mention it, Bob Mears reinforced it, and Mark
came up with the reason why it showed up after the tires were  "rotated".

When tire Rack sent me the tires, they sent one with a 45% wall  height,
while the other three had 40%! Thus, one tire had a slightly   different
diameter.  But, it was enough.  Being mounted on the front, I didn't
notice the difference in driveability until Jason reinstalled it on  the
rear. Once he determined the source of the problem, he put it back on
the front, and the problem has gone away!

The surprise was when I called Tire Rack to see what they would do  about
the tire with 3000 miles on it. I talked to a very pleasant young lady
who told me they would overnight a new one to my local installer (Dunn
Tire) and I should have it by Wednesday.  They would include a prepaid
return shipping label with the tire. I was on and off the phone in  less
than 5 minutes.

However, when I stopped by Dunn tire to alert them to what was  going on,
they now tell me that they handle the Avon Tech tires...they didn't  when
I first got them.  Tire Rack was the only place to get them on the  East
Coast.  Oh, well...not costing me anything <G>

So, -Reeves, Bob and Mark...you all win, the checks are in the mail  <VBG>.

Harley

Harley,
I love it when an experienced based hunch pays off.  Hopefully it
saved someone some time...

Cheers Reeves



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