Why so slim?

[MK999]

Originally Posted by sim

If both top (link) and lower (arm) are of equal length, you can have short arms and zero camber rise.

Track width changes radically with equal length links, especially short ones

[super__dan]

Course there is a train of thought which says centring the weight front to back is more important than side to side, hence the X6 which has the motor inboard so the moment of inertia when looking in plan is less than a conventional 2wd.

Stretching the weight right out front to back in my opinion will benefit in roll but may make jumps and front to back responce overbumps and ripples worse.

It's all a massive compromise and a guessing game, slim cars I like though, I liked Lee's a lot on the weekend.

Lastly I agree camber change is good, can help the rear break away in the middle of the corner as it leans over which can help you pivot to corner faster. Again it's all a compromise IMHO.

[MK999]

Originally Posted by DoughtyUK.net

sometimes camber change is a good thing, I have found that there is an 'optimum' lenght for suspension arms and that is less than 'longest'

All depends on where you're moving from and by how much, but by controlling the amount of change in camber you get by having longer links you can tune everything else more finely, some camber change is a good thing as when the suspension moves into droop position during lateral load transfer the wheels camber negatively slightly and that helps the wheel that needs it most (outside one) get the most possible contact patch while the body rolls without having it cambered in a straight line which would lose you a little straight line speed.

Ideally you should use a longer top and bottom link to obtain the same geometry you would get using a shorter arm to get the same camber change with less track with change, which we don't have the luxury of doing generally with RC cars, but this 'ideal' setup also ends up with a car with amazing cornering power but all the stability of weak jelly in an earthquake zone that no one without absolutely perfect precision and reflexes can drive... at the end of the day, the best setup is the one you can drive fastest really.

Also tire scrub I thought was any time that the tire is moving at a slower/faster speed than the car/ground underneath it? i.e steering with a locked differential with bad ackerman settings. Wheels moving in and out I'd express as "a change in track width"

I'm doing motorsport engineering next year at uni and been doing my background research hence the knowledge (or lack) of it and that's what i understand of it, feel free to correct though

/essay end

edit in response to prev post: everything you can do to your car is a compromise really, never ever get something for nothing (even if you go from running on 3 wheels to 4, more drag !)

[Dirt-Racer]

Camber change is beneficial when racing on loose dirt, i think.