SCORE ONE KARMA, KARL!!!
You will find, as demonstrated by repeated reports, that under load and at higher RPM's, the efficiency will increase even further! You will also find that an increased gap on the spark plug will give even greater gains.
My single cylinder is now at 300%. All I did was cut The Groove and regap the spark plug. Stock, it was .024". Now, it runs like a champion at .040"!
The wider the gap, the more power required to jump it. Since most coils produce way more power than is actually delivered, this will allow you to get the full benefit of the coil's rating.
Try that after you do your under load test and see what happens!
Great work!
Ron