Yes, it is worth the trouble finding the book. Try any university where internal combustion engines are on the curriculum. Everybody who owns the book has made a copy of it so it is fast to run it through the copying machine once again. You could of course make the publisher to reprint the book...
The reason for the dip in the torque curve may very well be a due to some kind of resonance in the intake or exhaust system. Variable intake or exhaust systems or adjustable cams may be the solution.
Some reasons behind dips in the torque curve and some possible cures may be found in the link...
Nice investigation work! IMHO the green spray should be much better than the red one. Fuel that is laying on the piston will not burn. You want air and fuel mixing in the combustion chamber. One problem you may run into is spraying fuel onto the cylinder walls but looking at your recent pictures...
When measuring the cylinder pressure at the indicator valve you will get a totally incorrect pressure curve. The compression may be fairly good but the combustion will (seem to) be delayed and the start of combustion too steep. There will also be oscillations in the pipe from the combustion...
