28* initial timing for a 318? How can that be?

StreetSleeper said

There is a not-too-old British book (I am not at home to take a picture) and the author categorized different combustion chamber designs (many of them every version of primitive open chamber) with corresponding initial and advance timing degrees.
Now I am just a keyboard warrior as inkjunkie would say, but with different inefficiencies in the combustion chamber, the initial advance gets larger-as I understand it.

Let the lords of wisdom correct me if I am wrong.

Click to expand...

Exactly.
One of many factors.
When AJ posts three paragraphs comparing 'dynamic' compression ratios, that's another factor.
It boils down to things that effect the flame development time relative to piston and crank position.
This gets back to the advantages of Shrinker and to some degree Tuner's approach: That is learning to think about the process from the inside out. In this approach we work toward understanding the burn and pressure development. We're still using data, but approaching relationships from the perspective of the engine. Good examples of this are in the snips from Tuner and Shrinker posted here.
As Rusty posted, its what makes them tuners. They can look at a problem with enough understanding to solve it.