Only to mention a few, and who'd forget the "ELTO", no one that ever raced with one, the "Drake", 2 cyl, but there are a lot of "current" engines, that if enough people of interest, would just get together, on a "box" to work from, and allow everything that met those qualifications, the days of building your own creation, might just spark some renewed interest, in a "do it yourself" race car, and still not be a "spec" class, or a rule of tire class, just good ole down home "brewin". I'm past doing anything, other than what I currently do, but hopefully someone will be able to. I still have 3-4 of the early 215's, both Buick and Old's, had a Hilligass car I was going to put one in, just for Vintage Racing, but time and money took that project away. Bob!