With hybrid turbo, 4bar map, downpipe without cat + dpf, stiffer valve springs , bigger cooler, transmission upgrade and Quqife.
Gives possibility to get over 400hp/1000nm.
OM642 is not so good engine, inline 6cyl is better.
The turbo might be ok.
It is the bad downpipe, that causes this situation, air (exhaust) do not flow properly.
That's why boost pressure do not rice - one reason.
The other is, that vanes are too open, after you have done your "things", the remapper have to do his.
If egr is clogged, remove the blockage, the ecu needs exhaust pressure information to make the turbo work properly.
Secondly, there is about 50mm throttle in the beginning of downpipe, chance the whole thing to 3" one.
Thirdly, you need a good cooler, that is something very different, what is...
Only different 250/220 cdi is that 250 have bigger injectors.
Quite easily 220cdi => ~500nm/230hp
Personally, I have a coupe 335d too, in fact two. The other one is true M-sport, the other is racer.
M550d has three or now four turbo's.
I have had a quite nice results for them.
Sorry to say...
If the 270cdi turbo is vacuum controlled, change is like plug and play.
Otherwise => little work.
If you are willing to get something more for the bigger turbo, you need a remapper, likely a good one.
You don't need to do anything for the exhaust as far as you use orig injectors.
Egr and DPF removed and softw.
No other mods
Glk OM651 220cdi is equal to 250cdi.
There is a possibility have even more easily, but fuel system do not support +300 power as stock.
No they shouldn't
200 cdi = single turbo, smaller injectors.
250 cdi = double turbo, bigger injectors
I have explained this earlier.
500nm demands ~88mg fuel/stroke and 200cdi's injector map ends to 90mg/stroke.
I think that injectors are the only difference.
In 250cdi the injector map there is values up to 120mg/stroke fueling level.
In all the other versions only 90mg/stroke.
90mg gives ~500nm, 120mg gives a ~ 600nm.
250cdi 4wd automatic
OM651 200cdi automatic
Practically all these Delphi ecu, one turbo models have same size of injectors and turbos.
So they all gives ~same power and torque, 500 nm/210 hp.
180/200 manual versions clutch won't last that torq, it must be reduced to ~400nm level.
OM651 220 cdi engine has a double turbo, same injectors =...
Not me, I am working mainly with MB/BMW cdi engines.
Old pre-camber engines with big power do not last, they smelt, too much heating stress.
Cdi´s have a lot of better using properites, lots of power/torq and they still works like stock.