For a less expensive speed, here is a vid of a guy running stock 550 brushed motors, 14 cells (16.8v), and 17/28 gearing. He it 23.9 mph.............thats cookin for a brushed villain. His first run is with 12 cells, then he changes to 14 and shows his readings at the end.
http://www.youtube.com/watch?v=BPuUA...eature=related