Caster angle: values and building approach

[Hrafn]

I'm working on a small (1:14 or so, 14-15 studs wide) car and want to include some caster angle in the front (MacPherson) suspension. Most real cars seem to use angles under 10 degrees, but what works well in motorized Lego vehicles? Should I exaggerate the caster in hopes of improving the steering's return-to-center tendencies? Even the smallest angle that's easy to achieve with Lego (22.5 degrees) seems a bit excessive compared to real cars.

Also, I'm hoping to build the front suspension and steering into a subframe that will be tilted relative to the main chassis. Does anyone have any advice on doing so, or examples they could point me to? It seems like the way to go, since it makes it easier to correctly position the steering rack. Previously I built an SLA suspension and just offset the A-arms longitudinally; that was compact but made steering a pain.

[z3_2drive]

In RC cars it seems that caster angle is greater than you would find in real life on models that take hard hits from extreme heights and speeds. As for a road car, work with whatever feels best. Advice? Make it strong and make sure the car doesn't bottom out easy, and don't put too much strain on weak parts. If it's a small car tilting the frame will require longer suspension travel to protect the bottom of the car. Some great examples are clarkdef's MOCs:

http://www.eurobricks.com/forum/index.php?showtopic=87118

http://www.eurobricks.com/forum/index.php?showtopic=97208

http://www.eurobricks.com/forum/index.php?showtopic=88753&st=25

And mine: http://www.eurobricks.com/forum/index.php?showtopic=88401

http://www.eurobricks.com/forum/index.php?showtopic=86913&st=250 (post 267)

[Hrafn]

Thanks, that's very helpful!