2014 Mercedes-Benz SL400

Place an order for a SL-Class roadster in North America and your choices come down to the SL550, the SL63 AMG (both with twin-turbo V8s) or the top-of-the-line SL65 AMG with a twin-turbo V12. But overseas buyers also have the option of a smaller engine, and soon American buyers will as well.

Until now that's been the SL350, packing a naturally-aspirated 3.5-liter V6 in Europe and other markets foreign to ours. But Mercedes is now replacing that model with the SL400, bringing the entire lineup into the turbocharged future.

The new SL400 packs the same 3.0-liter twin-turbo V6 as the E400 available overseas (not to be confused with the E400 Hybrid), producing 328 horsepower and 354 pound-feet of torque. That's still a good hundred horses and over 160 lb-ft less than the SL550, but comes in a good 26 hp and 81 lb-ft more than the naturally-aspirated V6 it replaces. As a result, the SL400 hits 62 miles per hour in 5.2 seconds – 0.7 secs quicker than the SL350 – and tops out at 155 mph.

In correspondence with Autoblog, Mercedes spokesman Christian Bokich confirmed that the new SL400 will arrive Stateside this fall, positioned below the SL550 as an additional option in the lineup. In the meantime you can scope out the full details of the European-spec model in the press release below.
Show full PR text
The new Mercedes-Benz SL 400: Start-up with new vigour
Apr 07, 2014

Stuttgart – The SL Roadster family from Mercedes-Benz is raring to go with a new engine. The SL 400 is now endowed with a six-cylinder biturbo drive system. Despite half a litre less displacement the output has risen by 20 kW (27 hp). Plus there are 110 newton metres more torque at its disposal. The price of the SL 400 starts from 97,282.50 euros (for the German market incl. 19% VAT).

As an automotive icon the Mercedes-Benz SL blends accomplished motoring at the highest level with exquisite style. Manufactured virtually completely from aluminium, the roadster also sets the standards in the category of luxurious roadsters with its numerous technical innovations. Not forgetting that the SL is entirely suitable for everyday use thanks to its retractable vario-roof. This makes it the all-rounder amongst sports cars.

In contrast to its predecessor, the SL 400 is not fitted with a naturally aspirated engine. Instead it boasts a six-cylinder unit with two turbochargers. Although its displacement has been reduced to three litres, the biturbo drive system develops a high full-load output potential with a charge pressure of 1.8 bar, and facilitates an extremely high torque of 480 newton metres at low engine speeds. It achieves 20 kW more than the SL 350. Its torque increases by 110 newton metres and is available in the engine speed range of 1600 to 4000 rpm. Plus the efficient six-cylinder meets the EU6 emissions standard.

SL 400 technical data
Displacement: 2996 cc
Bore x stroke: 88.0 x 82.1 mm
Output: 245 kW (333 hp) at 5250 to 6000 rpm
Torque: 480 Nm at 1600 to 4000 rpm
Fuel consumption: 7.3 l/100 km
CO2: 172 g/km
0-100 km/h: 5.2 s
Top speed: 250 km/h

Like all BlueDIRECT petrol engines the biturbo engine in the new SL 400 also works with a direct injection system with spray-guided combustion, which Mercedes-Benz was the first car manufacturer to offer in series production. The system pressure is up to 200 bar, the pressure being variably optimised according to the engine's mapping. Piezo injectors enable optimal mixture formation with up to five injections per power stroke. The third-generation direct injection is supplemented by rapid multi-spark ignition, MSI. How it works: Following the first spark discharge and a brief combustion period, the coil is recharged very rapidly and a further spark is discharged. The MSI system enables up to four sparks to be discharged in succession within one millisecond, creating a plasma with a larger spatial expansion than conventional ignition.

The rapid multi-spark ignition can be controlled to vary both the timing of the sparks and the combustion period to suit the relevant operating point. This provides scope for optimising the centre of combustion and improved residual gas compatibility. The result of this is excellent utilisation of the fuel with minimum emissions.

The SL 400 also offers two extraordinary innovations as standard: the unique Frontbass system developed by Mercedes-Benz transforms the luxury sports car into a concert hall, when the top is up and down, and the highly efficient MAGIC VISION CONTROL wipe/wash system takes water from the wiper blade to the windscreen as required and irrespective of the direction of wipe.