X2 no truer words can be spoken.and as far as motor why not build a 451 out of your 400 I understand they are cheap to build and are a strong running motor.I have seen them run well into the 10s.In a good chassis..and if you go with motor pleats will save $ a 10or11 sec.car can be dun petty cheap if you can do the work your self.......Artie