Boost pressure earlier?

"Besides using a chip, how could one meaningfully adjust the boost pressure start-up on a V6 TDI AFB engine to occur earlier? Is it possible to adjust the boost pressure control valve in a way that allows it to remain open for a longer period, or to have the VTG valve activate and remain active earlier?" What happens if I turn the control rod of the VT? Will I notice a change?

If there isn't enough exhaust gas to drive the turbocharger, there will be no boost pressure.

Edit: Stay away from the VTG if you don't know what you're doing. It can quickly become very expensive.

Okay, I'm not a novice; I'm a mechanic. I was just wondering if there's any experience out there regarding this. Maybe my wording was a bit strange. What could possibly be expensive? It's not like I'm going to be revving it excessively. But it needs to work, and I think I've seen something about this somewhere before.

Same as bastion.
All the older 2.5 models have this turbo lag, and the timing is normally optimally adjusted.
I can only imagine that the developing play in the shaft could be compensated for by some adjustment, allowing you to find the optimal point again.
However, this would need to be carefully controlled and monitored with a detailed LLD log, including before-and-after records and precise notes and markings of the rod.
So that you can eventually find your original, good position again, especially if things get even worse after the adjustment!

On my old loader, I also tried adjusting the settings. However, the play wasn't in the linkage itself, but in the VTG (Variable Transmission Geometry) mechanism. Adjusting it in that case also led to stronger overshoots. It was still better than the original state.
The engine should build full boost at 1500 RPM if given enough time, for example, in 6th gear while going uphill.

"By 'expensive,' we meant that this could potentially damage larger, more delicate components. What exactly are you considering?" In the worst-case scenario, it could be the charger; it's also possible it's the LD piping; however, it's unlikely but still possible that it's the LLK.