Worthwhile doing this every so often - and since it is cold outside (at least here in Cleveland) seems like a good time.
Many of us fly Club 40 and 424 with the TT40pro engine. Perhaps a little data exchange. No speculation, no theories, no guesses, no BS just some real time data you have personally collected, recorded or observed over the past flying season.
I have been pleased to see the enthusiasm and growth of the Club 40 group we have put together here in northern Ohio, and I have been pleased to help folks out as they learn and develop into the sport.
I have broken-in and setup at least 15 of these the past couple of years. Some for myself, most for other people. I know what the stock engine is capable of on the bench, and although 15 engines is not a statistically significant sample, I am going to claim it as such
There was some variation, but in general fairly consistant results.
Consider these all NEPRO configuration. Stock. Stock head gasket, stock muffler, baffle, not-messed-with fully functioning carb. Most newer models with stock rear bearing. Same 9x6 prop. Sometimes varied conditions (but real world averages out). Fuel 15% omega.
Two significant measurments were observed to be consistant: None of them peaked over 17,000 rpm with APC 9x6. All of them would peak over 16,000 rpm.
So allow me to open this up...
Provide your results. Prop, fuel, usage (424 or club 40), your geographical location, and typical observed rpm on the test bench, and rpm installed in the aircrft (sometimes different). If possible, the number of engines you race, and any noteworthy variation between them.
Let this start, and I will add some of my data into the mix.