Different designs of V8 engines

The design of a V8 engine gives designers plenty of room to play with in one key element: the crank arrangement on the crankshaft. This influences the characteristics of the engine. There are usually two variants in V8 engines: the 'cross plane' where the crankpins of the four pairs of cylinders are at 90-degree angles to each other, which AMG has used in all previous V8 engines, or the 'flat crankshaft', where all crankpins are on the same plane with a 180-degree offset ('flat plane').

If you look at the front of a cross-plane crankshaft, you will be able to identify the cross that gives it its name. The benefits of these crankshafts are superb smoothness and high torque at low rotational speeds. The characteristic sound is another hallmark feature of the cross-plane V8 engine. In order to make optimal use of the displacement and therefore the performance potential in the case of the 4.0-litre V8 biturbo engine, the AMG engineers have essentially moved the exhaust side into the hot internal V of the two cylinder banks in the V8 engine.

Uniformly oscillating gas columns for even more power

Another way of increasing performance is by using a 'flat' crankshaft. In the flat-plane V8 engine, it looks like an inline four-cylinder model – except for the wider crankpins, which have two connecting rods each in the V8. Ignition in the flat-plane V8 jumps from one cylinder bank to the next, which further improves the gas cycle. The characteristic firing order with a 180-degree crankshaft angle offset is 1-8-2-7 4-5-3-6. This creates uniformly oscillating gas columns in the exhaust tract and on the intake side, whose resonance can easily be used to increase performance. The greatest advantage is an even more agile throttle response.

The most powerful V8 series engine from Mercedes-AMG

The new GT Black Series engine is based on the AMG 4.0-litre V8 biturbo engine with dry sump lubrication, but it has been given the new internal code M178 LS2 due to the numerous modifications. It achieves 537 kW (730 hp) at 6700-6900 rpm and delivers a maximum torque of 800 Nm at 2000-6000 rpm. New camshafts and exhaust manifolds are adapted to the new firing order and improve the gas cycle further.

Both twin scroll exhaust turbochargers are mounted in anti-friction bearings, as in the top-of-the-range four-door AMG GT Coupé, which optimises their throttle response even further. However, in the Black Series, the turbochargers have been given a larger compressor wheel, meaning that both can deliver a total of 1100 kg air per hour. By way of comparison: The figure is 900 kg/h for the AMG GT R. 7000 rpm is not critical as a continuous speed, the speed is limited at 7200 rpm. And the larger intercoolers guarantee that they always keep the charge-air temperature within the best possible range. The unique standing of the new engine is also reflected in the engine badge, which is kept in black.

0-200 km/h in under nine seconds

What does the engine do for the AMG GT Black Series? It gives it a completely independent character, which is not only reflected in the type of power delivery, but also in its very particular sound pattern. And it enables highly impressive driving performance: the two-door vehicle shoots from 0 to 100 km/h in 3.2 seconds, and to 200 km/h in under nine seconds. The top speed is 325 km/h, although only on cordoned-off racetracks.

Modified AMG SPEEDSHIFT DCT 7G transmission

Power is transmitted to the rear wheels via the seven-speed AMG SPEEDSHIFT DCT 7G dual clutch transmission, which is located on the rear axle in a transaxle arrangement for optimal weight distribution, as is the case for all AMG GT models. It has been modified for use in the AMG GT Black Series and adapted to the increased torque of 800 Nm. The previous limits governing shift performance and response time have been extended, making them more suitable for racetracks.

#amg #mercedes
Get More Great Car Videos - Subscribe: https://goo.gl/BSIaFc