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Octane Rating

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I found this which for me explained octane rating very well.



"An octane rating (87 vs. 89 vs 92, etc.) is a measure of a gasoline's ability to resist detonation, which manifests itself in a pinging or "knocking" noise. Higher numbers indicate that the fuel can be compressed to a higher level before detonation / knock occurs in an engine, which occurs when. As described in "Detonation, Knock, and Pre-Ignition 101", detonation / knock occurs when air and fuel that is ahead of the combustion flame front ignites before the flame front arrives."





I was talking to a guy who used to fly the Super Constellation, DC-6, and DC-7. The 3300 bhp Pratt and Witney radials could only make that power with 150 octane rated avgas, and with 110 could only make 2750 bhp.






The Coconut King

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Yeah. I remember basic training in T-28s we had R-3350s IIRC with 2-stage blowers. We used 115-145 (purple) avgas. It was a neat airplane, but no longer does what we did since you can't get the gas any more. We ran 56" - 60" MAP on takeoff and 36" 2400 RPM on climb.


Them was the good old days - when men were men and sheep lived in fear :D

...Destiny's Plaything...

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