[Xracer]

The levels of tweak Mark has eluded to cannot be checked by eye, the car has to be fully laden and its wheels on a suitable tweak gauge, very small degrees of tweak will cause a pull on acceleration and/or braking.

A slipping diff is another culprit.

My 5.2 is not fully laterally balanced either.

Do be aware that a corner weight system can have inherent errors too, especially if each of the balance pads are at different heights relative to your setup board, this will cause an apparent tweak giving false individual corner weights, I had to modify my system to allow height and tilt adjustment of each corner scale to create an effective flat plane!

Ah the joys of our hobby!