[Raul]

Originally Posted by MikeJ675

find the most efficient motor possible(gas or electric) and put it/them(if more than one is desired) onto the lightest, stiffest chassis possible.

Then make a body to go over it with a cockpit of some sort.

I might lean towards a magmotor of some sort or possibly one of these- http://robotcombat.com/marketplace_motors_perm.html
if you feel like going for an overkill solution.

Perm-132
72 V Performance
Peak efficiency: 88.6%
Peak power:*34.3hp
No-load angular velocity:* 3590 r/min
Stall current:* 1440A
Stall torque:*38500ozf·in

...

1440 Amps at stall - Yikes!! Better use some automotive starter cables.