The next-gen models could be powered by a hybridized 4.0-liter V8.
Dubbed the M157, AMG's 5.5-liter twin-turbo V8 has apparently reached its potential in the recently unveiled S63 AMG. That's according to AMG boss Tobias Moers who told motoring.com.au the 585 hp and 664 lb-ft of torque it develops cannot be increased without threatening reliability. The AMG variants of the S-Class, due out in the next three years, and refreshed CLS63 and E63 will probably the best last to get the M157, which first appeared back in 2011.
Beyond that, we could see it replaced by a hybrid version of the all-new 4.0-liter V8 that is expected to power the AMG variant of the new C-Class, which arrives next year. Created by forging two of the A45 AMG's 2.0-liter turbo-four unit, the new V8 will also feature in the new baby-SLS 911 fighter. The 2014 Mercedes-Benz S63 AMG will arrive in U.S. showrooms this November priced from $140,425.