That Brillelli 46cc with an electronic ignition might be nice. Brillelli claims it will swing an APC 22x8 at 6850-7300 RPMs. I bet it could get a Mezjlick or something similar a bit higher. Base engine weight is also 9oz. less than the magneto driven one. This site linked by mattockx earlier states the 46cc Brillelli has a base engine weight of 46.5oz. I wonder if that's the EI or the magneto version. Shaving 9oz. off that weight would be nice.