Who says you can't teach an old diesel new tricks? Not Mercedes-Benz.
Apparently, some folks from the tri-star brand were sitting around talking about how much diesel technology has advanced in the past two decades and got the crazy idea of dropping a new Benz four-cylinder turbodiesel into an old 190D.
As it turns out, the advances in diesel technology have been pretty impressive. [With] the new OM651 four-cylinder turbodiesel, borrowed from the new C250, cranks out 201 hp (204 PS; 150 kW) and 368 lb-ft (500 Nm) of torque, the retrofitted 190D now has nearly three times the horsepower of the original and double the torque of the most powerful Mercedes-Benz 190 ever, the 190E 2.5-16 Evolution II.
Shoehorned into a twenty[-something]-year-old 190D, the new turbodiesel vastly improves the car's performance and fuel economy, not to mention emissions. The retrofitted car, dubbed the 190D BlueEFFICIENCY, now hits 62 mph (100km/h) in 6.2 seconds, which Mercedes-Benz says is an astounding 11.9 seconds faster than the original 190D. What's more, the BlueEFFICIENCY gets an estimated 48 mpg (4.9 L/100km), substantially better than the old car's 32 mpg (7.3 L/100km) and even slightly better than the C250's 46 mpg (5.1 L/100km). Of course, the new C250 is also nearly 850 lbs (385 kg) heavier, 6-in. (16cm) longer and 3.5-in. (9cm) wider and taller than the old 190D.
For Mercedes' part, they've done some fine work. The only giveaway - without peaking under the hood - is a small "BlueEFFICIENCY" badge on the fender behind the front wheels [and the digital display on the dash].
There's no word on the future of this car, as it was simply built to answer the question: "How might one make this progress (in diesel technology) directly tangible, in isolation from the equally profound changes in the safety and comfort of the car as a whole?" Well, they found a way.

Source.
Though this news is old, wouldn't it be nice to "officially" retrofit an old car at the hands of the original makers?

I love this. Its epic, It brings back the true Mercedes Benz engineering nostalgia. I wish there will be a rebirth of W123, W124, W201 and W126 all of which are high points of Bruno Sacco's works.

lomomike:
I love this. Its epic, It brings back the true Mercedes Benz engineering nostalgia. I wish there will be a rebirth of W123, W124, W201 and W126 all of which are high points of Bruno Sacco's works.

"A Mercedes-Benz must always look like a Mercedes-Benz." - Bruno Sacco.

DaimlerBen:

Source.
Though this news is old, wouldn't it be nice to "officially" retrofit an old car at the hands of the original makers?

I'd sign up for it!

Makes so much sense given the resources at their disposal, they would do the job at a price point that individuals would not match due to economies of scale to their advantage.

Of course they do restore cars from time to time, but it seems it is not a mass market thing