The fast engines are going to be Jett or Nelson. I have a BSE .35 myself. They are NO comparison to an OS. OS is stinky toe-jam compared to Jett. Jett's run best on 15% nitro, but will run on low/no nitro fine also. Drop 1" less pitch for FAI fuel.

RC car engines rarely ever have a long enough crank to get a prop on it. Besides, the big heat sinks on the head make them run way too cold with that much air moving over it. Best bet is a purpose made aircraft engine, IMHO. I've ran car engines for 15 years, 20-30% nitro and 38,000rpm would get expensive. My .28 monster truck engine burns 7oz in about 7-9 minutes.