Castor angle

[Dash]

I know castor angle is used to help with steering.

But what about castor on the rear tires?

Would having negative castor on the rear wheels have any negative effect?(if I eliminated bump-steer)

I would think not, but I am just a novice. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Adambomb]

Assuming no bump/roll steer, I can't imagine any effects, outside of perhaps changing the loading on the uprights and a-arms.

[Jevon]

The only thing I can think of is that if you do not have enough toe stiffness, negative caster in the rear will cause the rear to turn into the corner versus out of the corner. The former being oversteer and the latter being understeer. If there is enough toe change for this to be a concern than there are more serious issues. On the other hand maybe negative rear caster and a carefully planned toe stiffness could be used as a form of rear steering. Beats me.

[exFSAE]

The angle itself.. not really concerned. I'd just set the mechanical trail to minimize compliance-steer.

[STRETCH]

Only effects anything if you have compliance steer as already pointed out, but you would lose the independence in adjusting static camber and toe angles.