District VIII and Topeka have been flying "Sport Goodyear" also called "ClassII Scale Race" in Topeka for at least 15 years. Requirements are basically a profile of a Goodyear Racer, .15 bushed engine, (except Fox non-bushed engines are allowed and they pretty well are the norm). For a while the OS 15 was used, too. Fox 15s are still in production, about 75$ new, all their parts are still available from Fox.. No hot-gloves allowed, 10% fuel, 52 ft. lines and you're all set to race. Shutoffs are allowed.
To get an idea of what they look like, I've pictured my "Polecat", designed by Mike Greb. There are about three more "Polecats", including Mike's. Bill Bischoff flies the "OHM Special", "Lil Quickies" are popular with Melvin Schuette and Kevin Seaton.
Phil Dunlap and I have campaigned this very same airplane for about twelve years, they are very robust.