I hope that you can complete the protypes in due time.....Unfortunately, The US market is likely all electric by then. BUT the rest of the world is a different story, judging from the letters I receive routinely, almost daily

Rear exhaust has certain advantages regarding installations but is not absolutely necessary. The OS33 has proven that. Which ever arrangement produces the best mid range torque and throttle response is the best one to go with.

Nose ring boss is a big deal. No current gas engine has any provision for nose support of any kind. There are ways around the current situation and I've figured out one way to do it, but it isn't the best way.

Something new,prompted bywork Rob from UKis doingwith his engine mounting, I am looking at bringing the rubber iso mount to the front of the engine thus eliminating the need for a nose ring altogether. The experiment hasn't started yet but the design is sound.Nevertheless, havingthe stand off mounting lugs near the front of the engine and closer to the engine's CG will facilitate that work

Regarding headers and pipes, I'd be very happy with just a header made for the engine. But It's going to be very hard toequal ES Composites pipe overall performance (power and weight). Overall weight builds up fast with this size powerplant. A complete set-up of less than 3 pounds (1362 grams) will be best. Itis doable currently with existing parts made for sport flying mostly, so a dedicated effort for Pattern first (and sport flying second) should be lighter...

This can potentially be a breakthrough for the few of us that prefer the smell of Avgas in the morning. Just hope there is enough market response tofully developthe effort