I typed in the BSFC data from my new O-470-U engine manual.
Here is is. Leaned below 65% power. WOT. Despite the fact
the compression ratio of 8.6 is lower than a Mazda 13B,
at 9.5, you cannot run auto gas in this engine.
Not only that the Mazda can be leaned regardless of the power
level or setting short of detonation.
I obtained a whole hand full of owners manuals for several different
types of air craft engines and so far I have seen nothing less
than a BSFC of .45.
Paul Lamar
The AirCraft Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site.
http://home.earthlink.net/~rotaryeng/ http://www.linux.org
8,000 Feet 6.1 pounds per gallon.
RPM MP per gph HP Pounds BSFC
2400 21 0.74 12.7 170.2 77.5 0.455
2400 20 0.70 11.9 161.0 72.6 0.451
2400 19 0.65 11.1 149.5 67.7 0.453
2400 18 0.60 10.3 138.0 62.8 0.455
2300 21 0.71 12.1 163.3 73.8 0.452
2300 20 0.66 11.3 151.8 68.9 0.454
2300 19 0.62 10.6 142.6 64.7 0.453
2300 18 0.58 9.9 133.4 60.4 0.453
2200 21 0.67 11.4 154.1 69.5 0.451
2200 20 0.63 10.7 144.9 65.3 0.450
2200 19 0.58 10.0 133.4 61.0 0.457
2200 18 0.54 9.3 124.2 56.7 0.457
2100 21 0.63 10.7 144.9 65.3 0.450
2100 20 0.59 10.0 135.7 61.0 0.450
2100 19 0.54 9.4 124.2 57.3 0.462
2100 18 0.50 8.8 115.0 53.7 0.467
2100 17 0.46 8.2 105.8 50.0 0.473
12,000 Feet 6.1 pounds per gallon
RPM MP per gph HP Pounds BSFC
2400 18 0.64 10.9 147.2 66.5 0.452
2400 17 0.59 10.1 135.7 61.6 0.454
2400 16 0.54 9.4 124.2 57.3 0.462
2300 18 0.61 10.4 140.3 63.4 0.452
2300 17 0.56 9.7 128.8 59.2 0.459
2300 16 0.52 9.0 119.6 54.9 0.459
2300 15 0.47 8.3 108.1 50.6 0.468
2200 18 0.57 9.8 131.1 59.8 0.456
2200 17 0.53 9.2 121.9 56.1 0.460
2200 16 0.49 8.5 112.7 51.8 0.460
2200 15 0.44 7.9 101.2 48.2 0.476
2100 18 0.54 9.3 124.2 56.7 0.457
2100 17 0.49 8.7 112.7 53.1 0.471
2100 16 0.45 8.1 103.5 49.4 0.477
