Mercedes-Benz' New Turbo V-8 Engines

Today, Mercedes-Benz revealed more details about its V-8 engine lineup. The two new V-8 powertrains promise more power, improved emissions and better fuel efficiency.

The more important of the two is the new twin turbo 4.6-liter V-8. It will replace the successful 5.5-liter V-8 that powers most Mercedes with the “550” behind their class designations.

The engine’s decreased displacement is offset by the power boost of the twin turbochargers, which have a fairly high 10.5-to-1 compression ratio. The 4.6 promises 10 percent better fuel economy while producing 30% better torque. In the 2011 CL500, it produces 429 horsepower and 516 pounds-feet of torque. That’s 12% better power and 32% better torque than the outgoing 5.5-liter V-8 found in the 2010 CL550. This engine will likely find its way into the E-Class and the S-Class in the near future.

The second new powertrain is AMG’s new twin turbo 5.5-liter V-8, which replaces the regularly aspirated AMG 6.3-liter V-8 in the 2011 CL-Class, upcoming S-Class AMG and likely other AMG vehicles in a year’s time. It features direct injection and start-stop technology. This system still requires the use of a starter motor, but Mercedes says future systems may need no starter motor at all.

The 5.5-liter will produce 536 hp and 590 pounds-feet of torque in the 2011 CL63 and S63, which is 3% more power and 12% more torque than the outgoing 6.3-liter.

The 2011 CL-Class goes on sale in November and will be the first to offer both new engines. The 2011 CL550 will start at $114,025, with the 2011 CL63 AMG at $151,125 and the 2011 S63 AMG sedan at $138,875 (gas-guzzler tax and destination fee not included). For additional information about the refreshed CL-Class, go here.