John,
I've had pretty good luck wiring the R/C carb open on a couple of different engines. I don't wire them full open, but rather set the mixture while fully open, then reduce the opening to get the RPM to about 10,000 with a medium pitch prop. Typically the carb is then only about 1/2 open. I leave this setting and change props to get the flight performance I want. I only fly for sport, not competition and this has worked well for me. Typically one flip starts and almost never have to change mixture settings.
Paul