I will happily admit i know nothing about boost pressures etc. and intercooling and the likes, nor to be honest care. I am considering a new exhaust, but have my reasons for this.
The three things i said are what all the differences are from my own research. I believe the 126kw d40 had the variable blade turbo and obviously the computer to match, and the 140kw version had the heads as well.
What can be done to the 2.5 d22 to get up there in power, i don't know (besides chip of course, which still isn't as high). I personally have no interest in making mine a speed machine, hence why i don't have interest in learning of boost and crap.
Cheers
Mitch