I have a US model 190D 2.5 turbo that I'd like to get some extra power from. How much horsepower can the stock injection pump produce if I turn up the governor and full load adjustments?

How much power can I get before the stock turbocharger becomes too inefficient?

I am also thinking about ceramic thermal barrier coatings on the pistons and cylinder head to allow for higher power without overheating, does this make a significant difference?

Is it a good idea to have the local racing engine builder open up the intake and exhaust ports in the head for better airflow through the engine?

2.5 turbo can produce about 150-160hp with stock injection pump at full load. Intercooler is very recommendable if you increase load.

I think turbocharger can handle this 160hp but not more.

I can´t say about coatings, but people have taken over 300hp out of om602turbo without opening the engine. Efficient intercooler is a must with these numbers.

Hello Mitch! I have that same engine what I use before that new 606 turbo engine. I never use it with out ceramic coated pistons but I believe that coating realy helps and protect the engine.
I have ported head but valves remain stock size. That head flow about 20% better than original.
With modifield exhaust manifold, intake resiver and injection pump with 7 mm elements we took out 331 hp/5000 rpm and 529 Nm/4000 rpm

Thank you, Petri and Samuli. Diesel cars are rare here, and modifications are mostly for gasoline engines.