A guy on ebay sold his engines that were in a warbird twin.

I suggest you run it on a test bench. I found the airflow over the carb sucked fuel from the carb and made the top end go rich-lean rich-lean, it was not saging do to overheating.
One way to avoid that would be to make a curved intake (cut copper or stainless elbow silver soldered to a fender washer) bolted on the carb but it will be very close to the prop arc. I didn't want to bother.

The Heli guys were having problems with these engines sagging, and problems with Webra's too. I don't know what oil mix they were using but you would do best to use Mobil 2T synthetic at 25:1 for break in and then go to 32:1 after a gallon or so. You don't want to fowl that little itty bitty $17.00 plug with carbon!

Running the engine with a 13X8 or even a 12X10 prop will give it better cooling than a 14X6 during break-in. Use a tach and temp gauge if you have one. Tune it for 300 rpm rich during break-in and 100 rpm to fly, according to Keith himself.