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Old 01-21-2016 | 06:54 PM
  #1708  
Pretendpilot
 
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Originally Posted by chorner
No, the oil actually helps seat the rings properly! Has a dual purpose with the additive.

The 7-77 will be bogged down IMO if you run it under 5,500 on the ground. After break in you can run a 24x10 around that rpm or a 22x12 at a little over 6,000 and hit the power band nicely. Just my experience. If you run it in CDI it'll do 6,400 rpm on a 24x10 with methanol which I run it at... and handles it just fine (though I certainly don't pin it full on a dive). I guess depending on the plane and for a more "scale" flight you'd want less RPM but on my 32lbs Corsair, I bring the RPM up.
thx chorner. wow, that's a lot more rpm than I thought would be good for this engine. the manual says the rpm range is 1000-6000 with 6300 being max. I figured they are probably over-rating it, since the 4.8hp appears to be over rated (maybe for 6300 rpm?) sure would be nice to see a torque curve, but I couldn't find one.