Thats why gijoecam suggested the Formula SAE cars -- which, as I recall, run the 600cc from the Honda CBR
Indeed, the majority of them run 600CC bike motors, but in '02, there was a team that ran a turbocharged Harley twin-pot motor (until the turbo seal blew oit, at which point it put out enough smoke to fog the entire Silverdome parking lot in typical Harley style!), and a Japanese team that built their own 600cc V-8. There were a couple twin-pot motors there, but AFAIK, none of them ever fair very well.
When is someone going to teach those MiniBaja guys about chassis design!??! Those front shock mounts are right in the middle of the frame tube, instead of being triangulated like they should be.
There's a guy that has a 600cc snowmobile motor in his mini-B buggy running a CVT. He runs it out at Silver Lake here in Michigan just about every time I'm out there. IIRC, it's a water-cooled snowmobile motor... it's got some scoot to it, but the thing that stinks is that it has no reverse, so if he digs in going up a hill, he's got to get out, manually drag it out of the holes, and hope it doesn't roll back down on its own... Not much fun.
And, yes, I was the co-leader and brake system engineer for the 2002 LTU FSAE team. We took 13th overall, 8th in design, 3rd in Autocross, and I drove it to a 5th place finish in the skidpad.

Oh, and we kicked Cornell's arse in the Road and Track Triathalon!