Relationship between boost pressure and valve timing

Hello!

I have now resolved the issues I was having with boost pressure overruns, as mentioned in previous posts. Two vacuum hoses were leaking.

Now, let's get to the main topic.

With different settings of the valve timing, I observed that the LD (likely referring to a specific measurement or value) is approximately 0.1 lower when comparing, for example, KW 0° to KW + approximately 3°. Is this a more positive effect, or a less significant one? (The driving behavior is quite good.)
My thought is that if the initial air-fuel ratio is slightly low, more air will be drawn in, resulting in a better ratio of diesel to air.

Am I correct here, or am I making a mistake?

Please explain it to me.

Thank you for your expert information.