Prop size and Engine Tunning
I have have two questions . I have a DLE 35 RA , runs great in all respects it runs a 20x6 prop . Engine tune is perfect running at factory settings
1) If I went to a higher pitch prop ( 20x8, 20 x10) what would happen to the engine "tune" ? Would it be too rich or too lean? What would happen if I went a lower pitch prop , ( 19x8, 19x6, etc.) again too rich or too lean ? Also is no change at all possible.?Assume nothing else changes.
2) Does anybody have any knowledge about some thing called the " Prop Rule"? It is explained the following way- 2 times the prop diameter plus the pitch results in a number for that prop. Any other prop with different dimensions adding to the same number will have equivalent performance.
For example a 20 x6 and 19 x8 will both by the " Prop Rule " generate the same number - 46. Thus they are equivalent in all respects including how they load the engine , power developed and performance.
Anybody have thoughts or insights about this ? It seems like it should be true.