504 Rally car rear tyre wear

[Rally]

At the AMSAG rally last weekend i noticed that the rear tyres are still wearing out the inside of the tyre much faster then the outside edges . The inner blocks have being torn off while the outers are like new , I feel that this miss use odf the tyre must be having an effect on traction and counering grip.
This is rather annoying as I have tried , unsuccessfully it seems , to address this problem . I have modified the rear cross member by turning it back th front and mounting the arms on the stright edge of the cross member thus making the arms true trailing arms as opposed to the origional semi swing , semi trailing arms . Now the camber remains the same ( -1 ) thoughout the suspenion travel , The toe in is set to 2 mm , I thought this may solve the problem .

My question is what should I do to correct the tyre wear , more toe in , move mounting points on cross member . Any sugestions will be treated seriously .

 

[GRAHAM WALLIS]

Bill raised the mounting points of the front of the trailing arms on his Coupe. Fair bit of work on the cross member needed, gave a large increase in traction. Before this the arms sloped upwards from the cross member.

 

[309B6D]

"the arms sloped upwards from the cross member."
Was that after shortening the springs? It would be unusual for a trailing arm design to only use half of the arc of suspension travel available.
Raising the arm pivot point would help the arm pivot in its designed range.

 

[GRAHAM WALLIS]

No, raised if anything. It’s a coupe though.

 

[ThanosK]

My set up is 2.5 negative camber, 3 mm total toe, should be as close to 1.5 mm from each side as possible. You can use 1 mm shims in selected spots between the swing arm and the bearing carrier to achieve these values. Handling is excellent and wear on the inside is only a little higher.