Vaughn Mann wrote:

Tracy, help me on the figures here, If I'm running a 2.85:1 ratio, and my engine is turning 7000 rpm, my prop rpm would be 2,456 right?  This of course is almost supersonic tip speed depending on dia. of the prop. also.  But if I know that I would prefer to use my ultimate torque rpm on my particular engine, let's say it's 5000 as an example rpm, that may be not only more efficient but run cooler and of course longer lived (less wear) quieter and more practical for me I would need to slow my engine down but keep the prop speed of 2298, about the same (154 rpm dif.) as before right?  So in this situation the higher gear ratio of 2.176:1 would give me more versatility in the more efficient cruise realm.  But if I was a racing everywhere I went then I would want the ratio and prop combination that would give me the max hp rpm and the max prop rpm that would allow it for full throttle flying everywhere I go.  Does this make sen! se?

I'm flying a RV-6 with the 180 hp O-360 now but am looking to the conversion of the Rotary in the future if Avemco will cover me.  Funny how they will cover some if  they already have the rotary in it and others who want to convert, they seem to use that against us to jack the rate beyond practicality or cancel altogether.  Ironic how one has to weigh expensive ancient Lyc technology cost as opposed to high insurance cost because one wants to move into a much more reasonable and dependable and economic design isn't it?
Thanks for your thoughts,  Vaughn

 
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