Max length is 1m, as for the steering setup is seems to work fine with the servos on a y lead and the steering circle seems to look about right, due to the sheer weight over the front 4 wheels, i think the front wheels will need to steer other wise it'll just push on and ill have no control over steering, but i have yet to run it so we will see what happens
its certainly got the power for over 120 that were just a random number to give an idea, im hoping to achieve around 140/150, considering the record is 173 id be happy if i broke 100 on my first attempt