Last year when I had the suspension set up the rear cambers were not good. One wheel had 1 degree negative camber, which is fine, but the other was at 0.5 degrees positive. My car has the early reversed wishbone set up so the only way to cure this was to build in some form of adjustment. I've finally got round to making myself a pair of adjustable wishbones.



I used 25mm x 25mm box section instead of the original 25mm x 12mm.
The spherical joints are 1/2" x 1/2" and will have rubber boots fitted.
The I.D. of the round tube is exactly 1" so I'm making my own bushes from Superflex 1" diameter polyurethane rod, hardness 80 Shore. The inner sleeves will be stainless steel of 5/8" (16mm) O.D. and 7/16" bore to match the original GTM produced fittings on the rear swivel hubs.
The black finish shown in the photo is Hydrate 80 from Bilt-Hamber laboratories. It's a rust convertor but it also reacts and cures on new steel. They now need priming and painting.

Mmmmmmmm pretty.


Does your car not use a Mini subframe then or has something been done to a subframe to allow the wishbones to be fitted?

Iain

These wishbones replace the standard Mini bottom arms. The rose joint fits at the subframe end and the two rubber bushes fit onto a special bracket bolted to the Mini swivel hub to stop it steering. The standard Mini tie rod bolts to the little extension bracket on the wishbone.



GTM used this system then changed to the later version which uses a standard bottom arm and a track control link bolted to the subframe and the steering arm.

I also did make my own subframes but the geometry is exactly the same and they are interchangeable with standard 4 bolt dry subframes.

Ah right I see now. Seems as if GTM sort of went out of their way to complicate things though. Is it just to avoid the bump-steer you can get with locking links to the normal steering arm or is there some other mysterious advantage?

Iain

Yes, but they used this system before they went to the locking links. opinions are divided but I think that this system, when set up correctly, works well.

Has anyone seen the newly engineered tie bar produced by Alan Britton, Coupe and Rossa owner and proveyer of Rossa parts. The prototype, see picture attached, was seen at Newark last year and I believe that the final design may be available this year from Alan. The member ensures that the tie bar is positioned between the top arm fulcrum axis inboard and exactly in line with the centre of the top ball, outboard which should ensure no bumpsteer whatever.

Thanks Malc for the photo of my early idea.
But design has changed considerably since then.
The new arm is waterjet cut and then machined.
It is a direct replacement for the original steering arm but uses a spherical joint in line with the hub top ball joint.
There is a lug for mounting the drum handbrake cable and a face for mounting a disc handbrake caliper. Either can be
machined away if not required.
The standard RH/LH thread track rod is retained.
The inner spherical joint is mounted on an extension of the top arm pivot with a sturdy block fixed to the old plate mounting point
Machining is almost completed and kits should be ready for Stoneleigh. No price yet.

that looks like a very nice piece of kit! prices would be great! might have to make a trip to stoneleigh to see the set-up in the flesh!

That looks like it should do the job!

What you need is a marketing manager Alan. I'll talk to you later
Malcolm

Here are my completed wishbones ready to fit.



The outer bushes are 80 Shore A hardness polyurethane bushes machined from Superflex solid bar. They are 1" OD, 5/8" ID and 2" long. The pivot tubes are stainless steel and, at the moment, are on the car with the old wishbones.