Here's an excellent post of the parts one required to build a versachassis by Andrew Lawrence:
http://www.chiefdelphi.com/forums/sh...40&postcount=2
Our team will also be building a WCD as an off season activity:
http://www.chiefdelphi.com/forums/sh...d.php?t=129473
For a close look at the versachassis in action, look no further than team Copioli's reveal video:
https://www.youtube.com/watch?v=ffe8V9g1jmQ
https://www.youtube.com/watch?v=8tJMiGBpWHQ
We are using the same calculator that Brian posted to figure out what pulley and belt to get from WCP:
http://www.wcproducts.net/how-to-belts/
You decide the pulley size and the centre to centre distance to derermine the belt size.
From what I can see in videos and pictures, seems like team Copioli uses a 30 teeth pulley. Somebody correct me if I'm wrong.