a different rack and pinion question

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hangn0ut

hangn0ut

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Way back rack and pinons were installed on the front of k members,spindles swapped side to side. But there were problems. Anybody have the hows,what's and whys on this? I have always been curious about this. Thanks
 
No, the problem is the steering geometry. Ackerman angle I think is one. This gets into design problems I don't think anyone has solved with factory Mopar steering arms

Someone was making a setup for B bodies which mounted a rack in the "normal" position for the original linkage. Of course you'd need an "opposite turning" rack for that
 
Ackerman is built into the spindle/lower ball joint isn't it? Shouldn't be a problem unless I just have it all wrong! What I remember is the front wheels flopping over when backing up. Like with a whole lotta caster. Now that I'am familiar with,have a straight axle car with excess caster.
 
Ackerman might not be it. I'm simply saying it's a geometry issue. When you turn the parts around with the steering arms pointing ahead, it screws stuff up. There has been TONS written about it here. One thing documented "this problem causes" is interesting tire squealing when attempting to back up when in a turn.

Believe me, and you can BELIEVE me, if this was easy, it would be "doing done." There's been LOTS of threads on this here some time ago.
 
Yeah,that 'symptom' works for me. I will search the archives if possible.(never been there on this site). It isn't a matter of being smarter, I just need to know. Like these programs that detail the Titanic sinking or the D-Day landings. Interesting.
 
Well I have been looking at pics and reading posts for about 90 minutes now. So let me see how far I can stick my foot in my mouth.LOL. what I see is the loss of the arc of travel of the inner tie rod end as dictated by the idler and Pittman arms. A rack and pining would need to transmit steering movement via two arms that would describe arcs exactly as the factory arms do except these would be in front of the k member. No arcs, no geometry.
Of course someone else saw this a long time ago. And it probably isn't that simple. And its always easy to point out problems but to come up with a solution...... But it does feel good to scratch that itch.LOL.
 
IMO....ackerman and bump steer are two completely different issues.

reversing / flipping the steering arms/lower ball joints causes the ackerman (inside tire turns in a greater arc than the outside) to reverse......the outside tire now turns at a greater arc than the inside tire....effectively trying to roll the outside tire over and the inside without enough turning angle.

the bump steer issue is caused by installing a rack without changing the LCA pivot points to match the rack and pinions inner / outer tie rod pivot points.

IMO it is similar to installing a camshaft 180 degrees off....it will bolt up....but run like crap.
 
The difference is that the steering arms on the ones they put on a front steer do not have any points remotely resembling where they end up when you just take rear steer parts and flip them side-to-side.

A loose reference is taking a tight string from the center of the rearend housing and passing it through the tie rod end and lower ball joint. It should all be in a straight line whether you have a correct front steer setup or a correct rear steer setup.

Now take the rear steer parts and flip them side to side to make a front steer. You'll note that the string can no longer come close to passing through these designated points. That's why they make "front steer" components like there are on Mustang II's and late model Corvettes. They put the outer tie rod point where it needs to be for correct front steer geometry.

This is for ackerman. Bump steer is something else entirely.
 
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