Need help designing small RC car chassis?

[Lego Dino 500]

I've been fiddling around the past several weeks on a chassis design, and for the life of me I can't get started. I keep getting stuck designing the front axle. It's going to be independent suspension with steering, using 30X20W wheels and 56X26 balloon tires. Can anyone help? I'm trying to design it to be 16-18 studs wide. I'm hoping to make something small and light enough to get some decent speed out of 2-3 M motors.

[Saberwing40k]

Look at posts 86 & 88 of this topic:http://www.eurobricks.com/forum/index.php?showtopic=92099&st=75

[kb7]

Is that the width of the wheels included? 16 or 18 studs seems a bit on the large size for a fast car, don't you think? The chassis might be light enough, but a body will add a lot of weight for that size.

I'm currently working on a small and fast car that is about 19 studs in width total.