Mercedes-Benz has announced a new engine for the SL roadster, a 3.0-liter biturbo V6 unit that replaces the naturally-aspirated 3.5-liter V6 sold as the SL 350. The new model gets the SL 400 moniker to highlight the increase in power, as the new engine produces 27 hp and 110 Nm (81 lb-ft) more than the outgoing unit, rated at 329 hp (333PS) and 480 Nm (354 lb-ft) of torque.

Thanks to the biturbo system with a charge pressure of 1.8 bar, peak torque is available between 1,600 and 4,000 rpm. With the new engine mated to a seven-speed automatic transmission, the SL sprints from 0 to 100 km/h (62 mph) in 5.2 seconds, 0.7 seconds faster than the SL 350. Top speed remains electronically-limited at 250 km/h (155 mph).

Combined fuel consumption is also improved: the SL 400 averages 7.3 l/100 km (32.3 mpg US), compared to 7.5 l/100 km (31.3 mpg US) in the SL 350. CO2 emissions are 172 g/km, with the engine meeting the EU6 emissions standard.

Like all BlueDIRECT petrol engines the biturbo engine in the new SL 400 also works with a direct injection system with spray-guided combustion with a system pressure of up to 200 bar.

The Mercedes-Benz SL 400 is fitted as standard with the Frontbass audio system which is said to provide concert hall acoustics even with the top down. Also standard is the Magic Vision Control wipe/wash system that takes water from the wiper blade to the windscreen as required and irrespective of the direction of wipe.

The new Mercedes-Benz SL 400 starts from €97,282.50 ($133,375) in Germany, including 19 percent VAT.

By Dan Mihalascu

PHOTO GALLERY

Mercedes-Benz SL 400 (R 231), 2014