Just when we were thinking that the AMG V-12 engine had been consigned to the archives, Mercedes-Benz announces this phenomenal top-of-the-line variation on the new-generation SL roadster. With 621 horsepower and 738 pound-feet of torque, is this the most powerful car that can be bought from a major manufacturer's showroom?
MBUSA News Release
SL65 AMG V-12 Roadster will debut at NY Auto Show
Refined, exclusive performance
March 20, 2012 - MONTVALE, N.J.
Mercedes-AMG is launching itself into the 2012 roadster season with a vengeance. Arriving in U.S. dealerships in November, the new MY2013 Mercedes-Benz SL65 AMG V12 Roadster is making its world debut at the 2012 New York Auto Show. The AMG 6.0-liter V12 biturbo engine generates a peak output of 621 hp and a maximum torque of 738 lb-ft. The use of an all-aluminum body-in-white delivers a drastic weight reduction as the MY13 SL65 AMG is 254 pounds lighter than before. The distinctive front end is dominated by the new "twin-blade" grille with two blade-shaped fins and the lower horizontal bar in the front skirt in high-gloss chrome.
The SL65 AMG joins the SL550 roadster and the SL63 AMG roadster. The SL550 has a starting retail price of $106,375 and arrives in U.S. Mercedes-Benz dealerships in May. The SL63 AMG arrives in July.
"The combination of exclusive V12 dynamics and cultivated roadster pleasure was already unique in the previous model. We are certain that, with the new SL65 AMG, we have developed a stunning high-performance automobile beyond compare for a small, but loyal fan base," says Ola Källenius, CEO of Mercedes-AMG GmbH.
The intelligent lightweight design of the bodyshell also contributes to the reduction of fuel consumption. A key element in the improved fuel efficiency is the result of the AMG SPEEDSHIFT PLUS 7-Speed transmission, the ECO stop/start function, and improvements to the internal efficiency of the engine and alternator management. Despite a considerable improvement in fuel economy, the peak output of the AMG 6.0-liter V12 biturbo engine is up from 604 hp to 621 hp. The maximum torque stands at a mighty 738 lb-ft.
This unparalleled output provides amazing propulsion for the new SL65 AMG – acceleration from 0 to 60 mph takes 3.9 seconds. Top speed in the U.S. market stands at 186 mph. The key attributes of the AMG biturbo twelve-cylinder include its heart stopping acceleration, and seamless power delivery combined with a distinctive AMG V12 soundtrack. In short, the SL65 AMG captures the imagination with its refined, stylish performance.
Overview of key data:
SL65 AMG
Displacement
5,980 cm3
Bore x stroke
3.25 x 3.66 inches
Compression ratio
9.0 : 1
Power
621 hp @ 4,800 r/min
Max. torque
738 lb-ft @ 2,300-4,300 r/min*
Vehicle weight
4,299 pounds
Fuel economy
TBD
Acceleration 0-60 mph
3.9 s
Top speed
186 mph*
* electronically limited.
AMG 6.0-liter V12 biturbo engine with new technology
The AMG 6.0-liter V12 biturbo engine (M 279) is based on the previous M 275 unit and has been extensively developed for its application in the new SL65 AMG. New turbochargers with an enlarged spiral cross-section, new manifolds and wastegate channels optimized for airflow deliver an additional 17 hp. The multi-spark ignition with twelve twin ignition coils not only makes for smoother running, but also works together with a new, more powerful engine management and optimized cylinder heads to provide even more effective combustion. The outcome is fewer exhaust emissions, which is also in large part due to the optimized catalytic converter system.
The redeveloped AMG sport exhaust system incorporates a modified pipe layout for improved flow coupled with a weight reduction of seven pounds resulting from reduced wall thicknesses.
And it is not just the inner attributes of the AMG 6.0-liter V12 biturbo engine that are stunning – the engine also looks inspiring. The carbon-fiber and aluminum engine cover further underscores the exceptional nature of the powerful twelve-cylinder that lies beneath.
AMG SPEEDSHIFT PLUS 7-Speed transmission
For the first time, AMG is combining the 6.0-liter V12 biturbo engine with the AMG SPEEDSHIFT PLUS 7-Speed transmission. The wide ratio spread of the seven-speed automatic transmission delivers significantly lower revving and helps in the reduction of fuel consumption. A new fuel-economy torque converter, reduced-friction bearings and transmission oil thermal management further increase the efficiency of transferring power to the wheels.
The AMG SPEEDSHIFT PLUS 7-Speed transmission features four individual drive programs that can be selected at the touch of a button on the center console – Controlled Efficiency (C), Sport (S), Sport plus (S+) and Manual (M). The ECO stop/start function is always active in C mode. For the greatest sense of involvement and dynamics, there is the automatic double-declutch function for downshifting, as well as brief and precisely defined retardation of ignition and injection during upshifting under full load. The latter also reduces shift times.