I have been using the engine performance chart in Lycoming Operator's Manual (Curve 11260-A, revised January, 1997) for percent power calculation. Just yesterday I came across an April 2006 Kitplanes article by Dennis Douglas. In it, he described the newer chart published in 2000 that has very different data. For O-320-B and -E Series Engines the new chart is "Curve No 13381". The chart in the Kitplanes publication is not the original. Does anyone have a copy of the original Curve No. 13381? I would be interested in get it.
Here is a copy of chart from Dennis' article: