Hey guys I am building a 1/8th trophy truck and I am going to use an outrunner to power it, outrunner to wraith axle. I was wondering how big of one I need? It isn't going to be light due to its chassis being made of steel rod and a cage made out of steel tubing. I need a length and diameter so I can buy one to use in it. Can one of you outrunner guys help me out?