Actually, the reason I believe that it messes up the geometry is that the
tie rod's position varies relative to the ground. When you jack up the car
and the tie rod ends point down towards the road, the arc that they move
across pulls the wheels toe-in. As you lower the car the tie rods level out
and become almost parallel to the road pushing the wheels toe-out.
If the tie rod lengths were different then the arcs would be different
lengths and the resulting pull in of the swivel arm would be different for
each side. This would result in something like bumpsteer but it would happen
even when both wheels moved the same amount like when you go over a dip in
the road. You are holding the steering wheel which keeps the pinion in one
place on the rack. Therefore, if the rod lengths are different, the amount
either side pulls in will be different causing a steer. True, toe-in is the
total lenght but when you hold the steering wheel straight it is really the
changes on either side added togather. If they are different and you hold
the steering wheel the car would turn..
BTW, if your wheels are straight with the proper toe-in but your rack is not
centered by even 3/8ths of an inch you will loose about a quarter turn one
way and add a quarter turn the other. That last quarter turn of the wheel
kept me from making u-turns. If nothing is bent, the tie rod lengths have to
be the same on each side for the rack to be centered when the car is going
straight
rack
__________
/ \ tie rod
/ \
Chris reichle
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From: W. R. Gibbons
To: REICHLE, CHRISTOPHER
Cc: mgs
Subject: RE: Tie rod Ends / 64 B / 2nd try
Date: Tuesday,September 17,1996 10:49AM
On Tue, 17 Sep 1996, REICHLE, CHRISTOPHER wrote:
>
> Your tie rod ends should be screwed on the same amount on either side to
> keep the proper geometry in the suspension. The only reason that this
would
I think it is possible to have the proper geometry with the tie rod ends
screwed in different amounts--what determines the toe-in is the total
distance between the two tie rod ends. However, the pinion gear would not
be in the center of the rack with the tie rod ends adjusted unevenly. If
the clearances are different in the center and ends of the rack, then this
would be a minor disadvantage as there would be a bit more play than there
should be with the car going straight. If the clearance does not change
as the pinion moves the rack, then having the ends screwed in different
amounts should not matter, unless they are so far off that the turning
circle on one side is increased.
Ray Gibbons Dept. of Molecular Physiology & Biophysics
Univ. of Vermont College of Medicine, Burlington, VT
gibbons@northpole.med.uvm.edu (802) 656-8910
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