I'm pretty sure the only engine rule is it has to be a steel block, so the sky is the limit on cost, seeing as a typical ASCS Steel Block 360 costs 35,000 +. Crate engines aren't the way to go though, historically it does not work. You have to allow some form of ingenuity while still keeping costs low. If you want to run low buck sprint car racing, run 305's, or go run Waynesfield or Paragon. I'd like to see that Ecotec midget take off in this area, that could be a fun deal. But the only problem is that it is still a single engine provider.