Here's a comparison test between the two Mercedes AMG V8 engines: the previous 6.2-litre one and the current 5.5-liter biturbo. To test the 6.2-liter version they use the Mercedes C63 AMG, and for testing the five-liter unit they use the new SL63 AMG. The 2011 C63 AMG is good for 457 hp and 600 Nm of torque, while the 2013 SL63 AMG develops 537 hp and 800 Nm of torque. Even though the new engine is considerably more powerful than the old one, the result of this comparison might be unexpected.