AUTOMOTIVE developed the tried-and-tested 4.0-litre biturbo unit - despite it already being renowned for excellent driveability , power delivery and torque progression . The specifications were clear : Significantly more power than the previous flagship model of the AMG GT family , an even more agile throttle response , maximum torque - all of which meant that a radical change was needed in the form of a new , ‘ flat ’ crankshaft .
“ The new GT Black Series is our latest automotive highlight and continues a tradition established in 2006 . The sixth version of its kind is another AMG milestone and impressive proof of the incredible development expertise in Affalterbach . I am proud of the team who have created a unique super sports car , which now represents the absolute peak of our successful GT family . The performance , looks and driving dynamics of the GT Black Series are second to none . This project was a fantastic end to my work at AMG , for which I am truly thankful ,” says Tobias Moers , Chairman of the Board at Mercedes-AMG GmbH .
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 . An even greater advantage is a more agile throttle response .
Issue 45 2020 The Art of Luxury
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