Front Wishbones - Comments Please

[John P]

I’m building a McSorley+4 which is 4” wider than a book chassis and 1” wider than a Haynes Roadster.

Because I have two Haynes spec upper front wishbones, and because lower wishbone plates for the roadster are available from e-bay I have been looking at using Haynes wishbones on my car but with Cortina uprights as opposed to Sierra ones.

To see how this works out I have drawn up a Cortina upright with 2 degrees of negative camber and then arranged the lower Maxi ball joint so the centre line of the ball is horizontal to the lower suspension mount (as recommended on the Westfield site).

I then added a standard Haynes design top wishbone and finally measured the length of bottom wishbone which would be required to make it all work and this comes to 392.4 mm centre to centre which is only 20 mm shorter than the standard Haynes version.

The track is much wider at 1465 mm but this is virtually the same as standard Sierra track and at the back I’m planning to use full length Sierra half shafts in a DeDion set up.

It seems as though this would allow me to use the uprights and top wishbones I already have and give me a wide track front end which, I’m told, would give better handling.

Does this seem OK or have I missed something?

[Enoch]

I'm not an engineer but I would have thought that the other consideration will be regarding the steering rack. I would guess that if it comes out at about the same width as the sierra that the geometry would be better suited to the original rack. I would assume that the length of the wishbones has to be such that as the wheels go up and down the track rods don't pull as the effective length changes. Not sure if that makes sense and I am sure a more knowledgeable person will be along soon.