I jumped through some hoops to do it, but I do believe I have the steering sorted out. I might lose some of you on the mods I made to the steering rack to do it, but lets call it an experiment.
First, lets start with the steering rack mount. The front bracket was a weldment I ordered with the rack, the rear is just a short piece of 1.25" angle. I think some just use the front weldment, but I wanted this more solid as the load from the steering will not simply be end load on the rack as you'll see below. It fit perfectly on 2" by 1/8" bar. That might seem light duty, but it is possible I'll have to cut this out and redo it. With the bracket and the angle welded to it, it is actually quite strong.
is
I built these little end caps for the steering rack (I removed the heim joints). I didn't get any pictures of the process before grinding, painting, smoothing, etc... but it was made of small pieces of 1/4x1" bar, clamped and bolted to the end of the rack to take advantage of the flat machined ends of the rack. There is a 3/8 nut welded into the side, which is where the tie rod ended will be fastened. I built the nuts out of a coupling nut, and used my drill press and a flap disk to bevel one end... kinda like a small lug nut.
Why am I bastardizing this nice steering rack, one might ask. Good question, and this is where some of you might be thinking I'm ruining this setup, and I'm not sure you'd be wrong. The A-arms are parallel, that means there is no geometry to figure out what the steering rod should be to avoid bump steer - the rod simply should be the same length and mostly parrallel with the arms - pivot to pivot (in my mind). So I went to all this trouble to accomplish that, and still use the 11" rack (which has much more throw lock to lock than the 8" rack). I also already had the 11" rack (two of them, in fact). I'm not sure how much stress this will add to the rack, and if it can handle it or not, but we're giving it a go.
These plates were made to create ackermanns angle. I did the math simply by figuring the length from the front spindle on center the to rear axle, then did a little right triangle calculation. I arrived at 3/4" of an inch inward on line with the stock arm tie rod hole, and 7/8" inward 1/2" extended for the next hole. The aren't pretty yet, but I'm still working on this solution.
When I ordered the heim kit I got a standard panhard bar kit, with tube adapters. This tube is actually 3/4" EMT conduit (or maybe 1/2", I can't remember), and it works about perfect for 3/8" hiem joint tube adapters. I had to file out the end with a round file, then they pounded in nice with a rubber mallet. I'm just going to drill a couple spots and plug weld it. If I every have to redo these I'll be able to reuse the adapters. The EMT conduit is thinwall stuff, galvanized, and also lined with something. It'll be light, and believe plenty strong for this purpose.
Installed.
I initially attached the rod end on the top side of the spindle arm, but with the way these arms were made it was too high. After I installed them below it worked great.... little to no bump steer, visibly at least. There may be a problem at full lock though (somewhat created by the angle of the arm), but I think I know how I'll solve that.
This was better
I think I'll be taking off those brackets, doing some cutting and bending on the spindle arm, and welding in my "ackermans" adapters so they come off at a 90 degree angle from the spindle. The weird angle of the spindle arm can causes binding at the heim joint when fully extended in a turn with compressed suspension (or dropping, depending on which size). I think this could cause the tie rod to bind, and likely bend or break. I do not want my suspension to be limited by the tie rods, so I'll be working on ways to resolve that.
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