[Land-speed] TOE IN

[Skip Higginbotham]

Mayf
It is the caster complication that my little brain couldn't get past. 
So I made the steering arms the same length so there should be no 
Ackerman effect. Shouldn't be needed for a car that runs straight......
I DO know that weight on wheels (steering) is very critical to the 
directional stability of my car. It is not on a conventional 4 cornered setup.
I agree with the rest of your proposed method as well. Hard to draw 
straight lines through the frame tho....(-:(-:
Skip




At 08:36 AM 7/10/2007, drmayf wrote:
>Doug, I suspect that the length of the steering arm at the wheel would
>have to be changed.  This is a very common issue with the SUnbeam Tiger
>sitting in my garage. The ackerman angles are truly farkled. As you
>turn, the inner wheel turn some but the outer wheel turns more! Makes
>for lots of oversteer. Thias all came about because Carroll Shelby was
>in a hurry to get the Tiger back to Lord Rootes for production design.
>Put the steering rack in the way wrong spot and then added angles tie
>rod ends to cure the problem. Result...ok in a dead straight line not
>worth a plugged nickle on a turn. Many things tried to fix. Only thing
>is a new front end design.
>
>All, regards front end design for an in-line streamliner. On a four
>wheeled car in normal configuration, the front tires are separated by
>the track of the front tires. And as has been stated, if you turn, then
>the line drawn perpendicular to the wheel (or a line entending from the
>spindle straight out) strikes the line drawn through the rear axle
>(think of long extended axles). Then the outer wheel must turn  in a
>manner such that the line extended from the spindle meets the  same
>intersection point on the rear axle line as the inner wheel intersection
>line. SOunds complicated but really isn't.  Now I have not built or even
>participated in the building of a liner with inline steering wheels. But
>here is how I would do it. I would draw the line through the rear axle
>and put the car's centerline on it. Then measure up to the centerline of
>the rearmost steering wheel. Then scribe an arc down to the rear axle
>centerline. Do the same for the front steering wheel. If you do this,
>you will see that the front wheel turns less than the rear steering
>wheel. This would I believe be a correct ackerman.  Then I would fab up
>the steering arms to make this happen. I could very well be wrong in
>this however. It is my turn to be wrong this week...  Unfortunately this
>is really complicated by caster.  In order to work perectly the
>suspension would have to be straight up and down through the contact
>patch without any heeling over due to caster or king pin offset.
>
>Or you could run a bike...
>
>mayf