Stacey,
Box stock gas animal is 10 hp. Check out this article at http://news.4cycle.com/modules/sections/index.php?op=viewarticle&artid=11
He dynoed it against briggs flathead on alky (WKA R3 stoker) and the gas animal matches it almost exactly. The animal is cheep and bullet proof when setup for gas.
James
#45 Animal