Technical Tie Rod Knuckle - What is the difference?

Hey gang, I hoping to get some wisdom from some like minded folks. I put a rack and pinion on my 1951 Plymouth. All is well BUT the turning radius SUCKS so I want to fix it. I can accomplish this by SHORTENING the distance from the base of the knuckle to where the tie rod actually bolts into. Thus giving me more radius per turn of the wheel. This 1951 Plymouth Cranbrook has two DIFFERENT looking steering knuckles on each side. The Drivers side is straight, and the passenger side is bent upwards. These are factory parts so when I go to fabricate these, I'm pretty much doing it the same way but just shorter on the ends. My question is, should I bend the passenger side too? or can I just do both straight? will this affect Ackermann Geometry? I mean I know it will since radius is being affected, but im more so curious as to WHY the engineers did this. any clues?

 

The vertical distance will affect bump steer....but without seeing the other end of the tie rods, we can only guess at how it was designed.

you need to make sure the effective tie rod arc matches the suspension arc, or you'll get bump steer. This is something you see by looking at it from the front of the car.

this might help you understand what I'm talking about



btw rack and pinion conversions are not very HAMB friendly, and are also very difficult to do properly. Good luck

 

Squirrel, did you call tech support in India to get that video?

 

Just a note, shortening that distance will also make it harder to steer at slow speed. It will also increase high speed sensitivity making it easier to overcorrect.

 

If you're putting a rack in an old Mopar, you deserve to have to listen to that video!

 

Now that's just funny, I don't car who you are.

 

Is the steering radius the same both directions?

 

Just curious as to why you "put a rack pinion" in the car.

 

I've done a few racks in these old Plymouths before. They are considered off topic here.

Which rack you use will have an effect on the bump steer, and which power assist pump you may be using will have an effect on drivability.

I can probably help you some (its been many years and I no longer have pictures) but it will have to be done through PMs here.

Also in the tech archives, there should be a few threads on "rack & pinion on 46-48 Mopars" that will apply to your 51, but if you bring up the old thread and ask questions, Mark will delete it. It would be best to read those old threads then PM me and ask questions. I was 50dodge4x4 back then.