Dan Odenborg was a racing driver who was mainly active in the American club scene and digging into old racing results show him as having driven a Lola of some sort, but any other info would be more than welcome
At the 2005 Monterey Historics at Laguna Seca, the crowds were surprised by the appearance of what is probably one of the smallest racing cars around, and surely one of the least comfortable. It turned out to be a contraption designed and built by Odenburg in 1961, and being fitted with a 750 cc Mercury outboard boat motor, it competed in the Modified class H, (500-750cc) which would also explain the name of the car. Otherwise it does not really look explosive.
In Monterey the car was driven by James Jessup, who surely must have had some trouble to get himself in.