High-Performance V8 Engine Developed Totally by AMG

The engine that powers the 2013 C63 AMG Coupe and Sedan and SLS Gullwing and Roadster is the first engine developed entirely by AMG. A naturally aspirated 6.3-liter V8 producing 451 horsepower for the C class and 563 horsepower for SLS GT models, the AMG V8 is one of the most powerful naturally aspirated production V8s ever produced.

AMG Racing Success Spawns High-Power Production Engine

Known internally as the M156, the 6.3-liter V8 boasts a wealth of exciting features derived from AMG's highly successful racing efforts. Built almost completely from a high-strength silicon-aluminum alloy, the 6.3-liter engine features four valves per cylinder, variable valve timing, bucket followers (rather than rocker arms) and a variable-length intake manifold.

Crankcase Bedplate Instead of Main Bearing Caps

For greater strength and reliability, the AMG engine uses a rigid one-piece bedplate at the bottom of the engine block instead of individual main bearing caps that can distort or loosen at high RPM. With cast-in steel inserts for greater strength, the aluminum bedplate essentially sandwiches the crankshaft between two sections of the sturdy engine block.

A Racing Crankshaft

Made of high-quality 42CrMo4V forged steel alloy, a finely balanced crankshaft with six counterweights spins in five main crankshaft bearings. The crankshaft counterweights feature heavy metal plugs – a detail usually found only in racing engines – which means the counter-weights can be much smaller, increasing power by reducing rotational inertia and oil drag.

Each forged connecting rod is precisely "cracked" with the help of a laser beam, so the irregular fracture contributes to its strength when the two halves are clamped around the crankshaft. The connecting rods and lightweight pistons are matched for extremely close weight tolerances that contribute to smooth running at high speeds. Small nozzles in the engine block spray cooling oil onto the underside of each piston crown.

TWAS Twin-Wire-Arc-Sprayed Cylinder Bores

The cylinder bores feature a twin-wire-arc-sprayed (TWAS) coating, an innovative process that results in impressively low friction and running surfaces that are twice as hard as conventional cast-iron cylinders. The engine block and cylinder heads are made of cast aluminum silicon alloys (AlSi7 and AlSi17), which represent the state of the art in terms of strength, light weight and thermal benefits. First, a high-pressure water jet roughens the cylinder bores. Then two electrode wires and an atomizing gas form plasma under high voltage. In essence, the atomizing gas sprays molten metal from the wires onto the cylinder walls, where it solidifies, forming an extremely hard coating. A honing process finishes the cylinder bores, exposing micro-pores in the hard coating that will retain oil and ensure good lubrication of the pistons and piston rings.

Vertical Intake and Exhaust Ports

Adapted from racing designs, air passing through the engine follows a straight line down through the intake manifold into its hemispherical combustion chambers and out the exhaust passages. A patented dual-length intake manifold is part of the vertical intake and exhaust system. The engine shares no parts with Mercedes-Benz V8 engines.

Operated by a Bosch 9.7 engine management system, two electrically-operated internal flaps control air flow through a variable-length magnesium manifold. At relatively low engine speeds, intake air flows through long runners, which helps to maximize engine torque. At higher engine speeds, the flaps allow intake air to flow through shorter pipes for maximum high-speed horsepower. Two integral hot film air mass sensors behind the air cleaners provide the engine electronics with information about the density and temperature of the incoming air.

"Bucket" Followers Instead of Rocker Arms

The AMG-designed engine also features a sophisticated valve train, also adapted from the AMG racing engines. Each intake valve is 40 millimeters in diameter, while exhaust valves measure 34 mm. Twin overhead camshafts in each cylinder bank open the 32 valves via bucket-type followers. In other words, flat-top buckets sit directly on top of the valve stems instead of rocker arms, and the cam lobes sweep across them. This space-saving design provides a very stiff valve train that allows for large valve openings and dependable high-speed operation for maximum horsepower and torque. However, in contrast to racing engines, each bucket incorporates a small hydraulic lifter that automatically maintains valve lash, allowing for long service intervals and low costs.

Variable Valve Timing

The AMG V8 makes use of variable intake and exhaust valve timing to maximize efficiency and torque over a wide RPM range. Valve timing can be automatically adjusted within a range of 40 degrees using electro-hydraulic vane-type adjusters on each camshaft.

At part throttle, the valve timing adjuster keeps the exhaust valves open as the intake valves are opening, using this valve overlap to create internal exhaust gas recirculation, reducing exhaust emissions and improving fuel economy. However, approaching full throttle, the camshaft adjustment optimizes valve timing for maximum power. The intake cams are driven by a double chain from the crankshaft, and small gears on the intake cams drive the exhaust camshafts.

One Man, One Engine –Individual Hand Craftsmanship

Each new AMG engine is hand-assembled one at a time by an expert craftsman at Mercedes-AMG in Affalterbach, Germany. Mercedes-AMG follows a philosophy of "one man, one engine," which means that a single technician – identified by the signature plate affixed to the engine – is responsible for the complete assembly of an AMG high-performance engine from start to finish.

With the utmost care, the craftsman installs each and every part – from the crankshaft, connecting rods and pistons to the intake system, wiring harness and oil fill-up. Each new engine is bench-tested to ensure consistent quality and maximum performance

About AMG

AMG has been the high-performance subsidiary of Daimler AG since 1999 and is located near Stuttgart in the country village of Affalterbach, Germany. AMG employs more than 600 specialists in development, production and administrative areas. AMG develops each of its models, including the transmission, chassis, brakes, aerodynamics, interior and – most importantly – the engine.

AMG engines are the product of a surprising combination of cutting-edge technology, computer-aided design and old-fashioned hand craftsmanship. No automobile capable of eye-popping flat-out performance also displays such a docile nature in every-day driving. Each engine is produced and tested at AMG's headquarters in Affalterbach, and AMG models are assembled at the main Mercedes-Benz manufacturing plants.

With more than 50 percent of AMG sales, the U.S. is the top market for AMG worldwide. While all Mercedes-Benz authorized dealers offer AMG products, about 25 U.S. dealerships serve as AMG Performance Centers, which include specially trained staff, uniquely branded point-of-sale materials and highly popular "AMG Performance Tour" weekend driving events. AMG also offers track-based Driving Academy and AMG Challenge programs.