Toe-in / Toe-out

See also Suspension

I'm not the definitive expert on these matters, but AFAIK front toe is usually set so that in normal driving condition the wheels point straight ahead. A Caterham is RWD and so when driving forward the front wheels are pushed back and a little toe in is needed to push front wheels to point straight ahead. A Mini is FWD and when driving forward the front wheels are pulled forward and thus a little toe out is needed to keep front wheels straight.

Changing toe settings will affect steering feel and not much else. adding toe-out will make a car turn in quicker and make the steering more sensitive. Too much toe-out will cause darting while braking heavily and an unsteady feel at high speeds. Too much toe-in will give the steering a very lazy feel. Toe settings also need to take into account the amount of Ackermann angle designed into the front steering arms. Bump steer is when the car darts to one side or the other when one wheel moves up or down more than the other wheel. This is usually a design of the suspension, or a bent steering arm, or modification (ie. lowering) that alters the geometry too much. Bump steer happens when the up and down arc of the steering arm and the suspension arms are of a different radius.

Toe-out in front wheel drive cars is to get the wheels to a close to zero toe setting when acceleration causes the wheels to move forward slightly due to suspension bushing deflection.

No toe-out in the rear!!!! If most cars have toe-out added to the rear it can cause serious oversteer, sometimes snap-oversteer when letting off of the throttle.

Source: Haynes Workshop Manual 1969 to 1996 up to P reg (UK) (added 25 11 02)

front 1.58mm toe out

3 +/- 1 degrees positive castor

2 +/- 1 degrees positive camber

rear 3.17 mm toe in

0.5 to 2.5 degrees positive camber