The new Mercedes-Benz S250 CDI BlueEFFICIENCY is equipped with the first four-cylinder powerplant in close to 60 years of S-Class history but the engine move wasn't decided lightly.
Still recognized as a hotbed for Mercedes engineers to incorporate new and developing technologies, the S-Class had never known four-cylinder power until now. The S250's 2.2-liter diesel inline-four puts out 201 horsepower and 369 pound-feet of torque. Peak torque is available at a diesel-appropriate 1600 rpm thanks to its inherent oil-burning characteristics and staged twin-turbo system. Diesel fuel is pressurized up to 2000 bar (29,000 psi) prior to injection and the S250 BlueTEC is capable of 41.3 combined mpg on the New European Driving Cycle. Emissions are rated under 0.53 pound per mile, a figure more commonly seen with the compact cars available today, and a seven-speed automatic is employed to handle transmission duties.
"Some might call this sacrilege -- we call it progress," Daimler boss Dieter Zetsche relayed during an S-Class press presentation. "We want to be efficiency world champions...and we will be."
The move to transplant a four-cylinder engine into the S-Class was "previously unthinkable," per Dr. Z's claim, but inevitable given the circumstances. The 2.2-liter diesel engine is just one of many powerplants available overseas and the United States is in line to receive the 2011 S350 BlueTEC next year. The S250 is priced in Germany from 71,876 euros, or $100,175 according to today's currency exchange rates (including a 19-percent value-added-tax).
Now the question remains whether the S250 will be available in the U.S. Given the snails pace that diesel passenger vehicles are entering the market, we wouldn't expect this four-cylinder S-Class in the near future.
Sources: Automotive News (Subscription required), Daimler