Agreed Stu but you'll still be suprised at the effect C.R has on the engines efficency against rpm/load.

It's too complicated to discuss here but I do NOT agree with high comp and least ignition advance as the best method.

Yes, less ignition by definition implies greater engine efficency but it does not always result in a net gain.

This is why I am a big lover of low comp engines as I have a prefered set of parameters I like to keep within.

The rest is very much secret squirrel.