That's why they have classes.
Accepting the limitation is what makes it art. What I'm thinking of is a belly tank with the VW boxer cylinders and heads sticking out of the nose like a light-plane with no propellor, front wheel drive like the XR-3, long axles with tall, narrow, rock-hard front tires for traction, a reclining cockpit like an F1 car, and the two rear wheels in tandem, (like the Speed Demon has in front). If you could get any traction, it would go real good.
If the rear wheels need to be open, it could be done similar to the Junker G.38 landing gear.
_____
Edit [20131012]: Like this
This is not well developed, yet; the proportions of the tires to the body are eyeballed, etc. But the idea basically is to have the same cross-sectional area as a P-38 tank (36" dia), but since I don't like the idea of a circular cross-section so close to the ground, it's more triangular, like a shark or ME-262.
The flat-4 boxer is in the front with exposed cylinder heads and a corrugated dry-sump tank for an external radiator. There is zero internal ducting.
The front tires are on 33" wheels with open spokes, but with a V-shaped rim like bicycles use. This is to improve cross-wind performance. The VW transaxle would be inverted to put the axle centerline above the crankshaft centerline (this saves needing to flip the ring gear). The rears are on an independent truck that is torsionally sprung.
I roughed in a Golden Submarine-style turret but I suspect that forward vision would be video on a head-mounted display. Driver is to the rear so they can tell when they're driving sideways.