GaRCfield: Are you really gaining any benefit from operating that engine at 13,000 RPM besides noise? Even though engines are rated at a certain HP at a certain RPM, (1.6 HP @ 16,000 RPM for instance) that is not a practical RPM range for most engines. Yes, I know, you are not reaching 16K, however, I've found that there are some that just begin to operate well at that RPM, but the general use engines that we use, OS engines for instance, normally like between 11,000 and 12,000 RPM and will run on forever with those numbers.

I prop'ed my smaller planes with that RPM in mind and never had a problem with performance.

Just wondering.

CGr.