By the stripes on the hood it looks like one of the original Dan Gurney All American Racers AAR Cudas.
http://www.trans-amseries.com/Drivers/AndyBoone.htm
After racing my Viper in SCCA for a few years I learned to repsect what lack of weight can do in a race. A 1000 lb car with 100 hp is the equal if not better than a 4000 pound car with 400 horses. The record holder in the class used to run was a Lotus Elan, probably weighed 1800 pounds total compared to my 4000 pound Viper.
That said, the guy in the BMW was an a-hole in terms of track etiquette. You don't pull into someone as they are passing you. This looked to be some type of vintage event and if I was the Cuda driver I would have have pulled into the pits after the run, walked into the booth with that tape and showed them all. And if that didnt sway their opinion and forced them to pull the guy's event registration, there is always the pit manueaver on the next run. (but turn the camera off first)