GU Y61 2.8 Power Isuue and smoke after new Head Install

GU Y61 2.8 Power Isuue and smoke after new Head Install
Hi Guys

Hope all you guys and girls out there are enjoying your Patrol.

I have and old girl GU Y61 2.8 Diesel which blew the head.
I replaced with a new one and timed it all up and had No power and blew smoke like id made a smoke bomb lol.
Couldn't work it out thought maybe I had timing out so took to my mechanic who re - checked the timing and checked a number of things and suggested changing the turbo so changed it with no difference,
Did some research and advanced injector pump, got a-lot more power still not what I had before, runs well at 100 klm on highway but still smokes.
Going up hills still dies. Around low 60 klm around town and smokes a lot and takes awhile to gain power.
Wondering if anyone has any ideas how to fix or point me in right direction.
Many Thanks

Cheers Dazz76

A restricted air intake or exhaust system can impact the engine's performance. I think you should check the air filter to ensure it is clean and not obstructed. Inspect the exhaust system for any blockages or leaks that could impede the flow of gases.

geometry dash scratch