Highest combustion temperature is present at the highest voltage.

Fuel injected at that point or lets say the bulk of it should give maximum energy output to engine.
Or maximum utilization of fuel if lucky.
Certainly the most available power. Old 300d, this applies to the direct relationship of point of fuel introduction.

Not to be confused with what the gentleman is trying to accomplish with his pump out of sequential time.

Hope he ignores it for the time being.
Others may put it more succinctly.

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