Alterations to my A30's rear axle
Ever since I got my car on the road (2010) I have not been entirely satisfied with the rear suspension. The problem lies in the slightly wider tires that I have. They are fitted to "mini lite" replica wheels and there is simply not a whole lot of room in the wheel well. This has proved to be a problem in tight turns when I have some extra weight to the rear of the Austin. This makes the tire rub on the inside of the wheel well. With slower driving it is certainly possible to drive but this is obviously not ideal.
There are of course many ways to address this problem,
1. Grinding down the inner flanges. (has already been done to my car)
2. Bending the flanges inwards (this creates a friendlier edge)
3. Pushing out the wheel arch with a piece of wood and a jack. (would crack my paint job)
4. Constraining sideways movement with a panhard rod.
I have been thinking about and I finally decided that I want to try a panhard rod. My father also enthusiastic about it and together we set the goal to have it finished before the trip to the 2015 International Rally. This also made it possible to have a bit more weight in the car for the trip and this in turn meant that one extra person could come along.
Of course I had a number of requirements for this construction. The main requirement was that I did not want too much to change the car itself and that I could undo the alteration without too much effort. With my online research I have seen a lot of panhard rods on similar cars and have also seen a 'kit' that can be purchased. Most of these do require welding to the rear axle to add a mounting point to it. I think this is not the most elegant solution so I dove under the car to devise a removable support.
The following pictures are examples I found during my on-line research. This one is by a fellow Dutch club-member and I like it a lot, in the end I went with a setup that I thought was simpler to make.
This design uses two arms that are attached to the under and top side of the axle. This means that it needs other types of springs.
Very elaborate, it does ensure that the axle stays in the middle of the car through the entire length of the suspension.
Here a support is fitted to the underside of a car, and this is similar to the moto-build setup that can be purchased
This is the set that cab be purchased from moto-build
All the measurements were punched into a 3D CAD package and made drawings (PDF)
to fabricate the supports.
This support requires a plate between the shaft and the spring assembly this can be fitted thanks to a set of long "U" bolts, which I obtained.
You are of course free to use this material, but at your own risk.
Turning conical mounting bushes for the steering rod.
The parts, cut out as per design
The mounts all welded up
The other side of the mounting brackets
Eventually we fitted our creation under the car. The set consists of two brackets and a modified steering rod (see photos), provided by my father.
The part that goes around the leafspring
The part that is bolted to the underside of the boot floor
An overview. After installation of new stiffer springs and Panhard rod we left, after a few test runs, for England and I can report that I have not heard any tyre rubbing the whole trip and we had 3 persons in the little Austin with some luggage. My brother was happy that he could also come to the International rally because of my improved rear suspension setup.