Wouldnt the front steer wheels and motors be difficult to engineer especially if you were using gears and chains?

I would be more inclined to spend a bit extra and try to get the E-TEK motor by briggs&stratton from America, it has approx 15hp at 48v or around 12kw

Heres a link to some that sell them http://www.robotcombat.com/marketplace_etek.html

Although not so good for solar cars due to lower efficiencies compared to brushless, far more powerfull for size and it doesn't require the complex brushless controllers (a controller is still nessesary but not as complex or expensive) 

Here's a machine that uses one

http://www.thunderstruck-ev.com/jackal_home.htm