this may be or may not be any different but when i used to race model powerboats i had a 67 size outboard engine fitted with a 2 oz header tank set level with the carbs venturi and the main 10 oz tank was down lower about 3 inches, the engine never failed . i think the inverted flight could be a different story . if you have room to fit a very small header tank in the engine bay and keep your main tank at the correct level this would work fine.