New CLS AMG will come with the recently introduced 5.5 liter, twin-turbo V8 which will debut in the S63 AMG this summer.

A chance to hear the upcoming Mercedes-Benz CLS AMG's new 5.5 liter bi-turbo engine roar while doing some track testing at the Nurburgring circuit.

Gone is the naturally-aspirated 6.3 liter V8 from the four-door sport coupe, although reports are that the model will keep the CLS 63 AMG name. The new CLS AMG will come with the recently announced 5.5 liter, twin-turbo V8 which comes in two power configurations.

The 'standard' iteration is 544 PS (400 kW / 537 hp) and 800 Nm (590 lb-ft) of torque. An AMG Performance Package upgrades the engine to 571 PS (420 kW / 563 hp) and 900 Nm (664 lb-ft) of torque.

That engine will make its debut in the Mercedes-Benz S63 AMG this summer where it will deliver about 25 percent better fuel-economy over the previous 6.3 liter V8. It's expected to sport similar numbers for the CLS as it does in the S63 AMG - 10.5 liters/100 km fuel-economy rating and the 0 to 100 km/h sprint completed in just 4.5 seconds.

The new CLS AMG is expected to make its debut at the Paris motor show this October.

Gallery: 2011 Mercedes-Benz CLS AMG Burns Rubber on Nurburgring [video]