CAV ESP vs. Bosch: AEF Motor Comparison

Hello.
I have a question for the mechanics.
I just installed a turbocharger on my Post Polo 6N with a naturally aspirated 1.9 TDI engine (AEP). So far, everything is fine, and it's running great. However, I'm now experiencing some problems:
Inside was a Lukas CAV ESP fuel injection pump, and I cheekily swapped it for a Bosch pump from a Golf 2 TD, along with its injectors (ESP number: 0460494182). My initial impression was that it ran a bit harshly. So, I reduced the fuel delivery start from 90 to 80... and it ran best at 60. It still made a bit of noise at idle. Then, I asked our 'pumpen fuzzi' (fuel pump expert), a Bosch technician, and he told me that the pump wasn't suitable for the engine at all and couldn't be adjusted. Since I don't always believe that right away, I'm asking the experts I know if they have any thoughts about this pump in this engine.
Regarding the Golf 2 ESPs with LDA in general: Is it true that many of these ESPs have problems with boost pressure at higher RPMs? Is this repairable? My Golf 2 feels like that might be the case. My Golf 2 GTD does the following: Under full load, the boost pressure reaches about 0.9 bar, but as the higher RPMs are reached, it drops again – down to about 0.6 bar at full throttle (e.g., on the highway). It's understandable that the airflow might be worse at higher RPMs, but is the effect this drastic?
That's all from me for now. I would like to add some comments about all of this.
Best regards from Danny, the mechanic.

Hi,

Is the AEF engine a direct injection (DI) or a swirl chamber (WK) engine?

If it's a direct injection system (which I assume it is), you won't be able to do much with the pump and injectors from a waste-knock engine (G2 TD). In that case, your Bosch master is correct.
In the Polo 6N (from the 1995 model year onwards), I am not aware of any naturally aspirated (WK) engines being offered, only direct injection (DI) engines (SDI, TDI).

It actually has an engine with swirl chambers. The car is from 1996. At the post office, everything is different. By the way, we disassembled the engine and completely re-sealed it - and we also installed a longer transmission. As I said, it already runs quite well, but the fine-tuning is causing problems, because only then does it make sense to adjust the pressure and the LDA.

danny wrote:

It actually has an engine with swirl chambers. The car is from the year 1996. At the post office, things are just different.

Ah, a company vehicle... okay, forget my previous post.