There you go, that explains some of it. At 17oz that is still a light 60, but closer to the typical 60 size engines. I do not consider it a full 60 because Bob Brassell has said it is really an overgrown 46 and to not look at it as a full sized 60, and if he doesn't know his own product, who does? I would say that ANY engine that swings an APC 11x6 at 15,000rpm should be perfect for ballistic pattern use.
Mark