G'day to all,
It is a long time since i have posted here as my 57 Chev project has been on the back burner for a few years. In the past couple of months I have been doing a bit and enjoying the challenge. After a failed attempt to install a RHD Jeep steering box I decided to use the Datsun 260C box which has been used by others here with some success. I was keen to ensure that there was minimal bump steer with the new installation so I have tried to replicate the height and position of the drag link on the LHD cars. It seems that a lot of RHD conversions done in the past have lowered the drag link and even Rack and Pinion installations are lower than the original drag link height. This could result in bump steer as the arc of the tie rod is different from the arc of the bottom Wishbone (Control arm) under bump condition. I installed my old manual LHD steering box, LHD drag link, and Idler arm in the factory positions. Then I made up an angle iron cradle supported off the pivot points of the lower wishbones. I positioned the LHD drag link in the straight ahead position and bolted it to the cradle with angle iron brackets through the tie rod pivot points on the drag link. This effectively locked in the position of the pivot point for the tie rods on the left hand and right hand sides.
Then I removed the LHD drag link and installed the RHD drag link on the same tie rod pivot points.
I then bolted the Chev RHD pitman arm to the New Datsun steering box. This involved removing 4 splines from the Datsun sector shaft to allow the Chev RHD pitman arm with 4 master splines to be bolted on. The ball on the bottom of the RHD pitman arm was then installed into the RHD drag link and the cups installed to lock in the position of the pitman arm ball. The steering box was then rotated up against the chassis rail and the holes marked on the chassis rail. At this point I noted that the top front bolt hole on the steering box was too high and would not be able to be installed in this position. I then made up a 12mm thick plate and bolted it to the top hole by cutting a thread in the top hole of the steering box. I then drilled the plate in 3 locations where the bolts could be installed. The middle location went through the bottom mounting hole on the steering box
The top hole on back side of the box was also above the chassis rail. I made up a bracket from 75x75 angle welded to a 5mm thick plate. I was reluctant to weld onto the chassis as I hear that some Automotive Engineers here in Australia do not like welding on the chassis. The photos below show the fabricated bracket.
The box was then bolted up using crush tubes which I juggled into position inside the chassis rail. These crush tubes were also used on the idler arm bolts on the left hand side.
The result is the steering geometry is exactly the same as originally designed by GM so hopefully bump steer will be minimal. All a bit long winded but hopefully this may help some others with RHD conversions.
During my investigations for this I learnt quite a bit about bump steer and its causes.
All the best and good luck with your project.
Last edited by oldmanmonaro; 07-22-2019 at 05:53 AM..
Good to have you back on here.
I have a template for mounting the box I could have copied it for you. but I am away up north at the moment.
The way you have done it is the same way a mate did a rhd conversion on an El Camino for me years ago. He set the tie rod ends in place and then modified the drag link to suit - after his mods were done he had the drag link xrayed to ensure the welding was OK.
Just out of curiosity, size-wise how does this box compare to the 500 box? Or the 605 for that matter. Wondering if it would afford anymore room for headers.
The Datsun box is a bit higher than the 500 / 605 box. That is the sector shaft is longer. Other dimensions I would think are similar. I don't think this box would provide any more space for headers. I would have used a 500 /605 box if there was one available in right hand drive.