Christian Enderle is Head of Engine and Powertrain Development at Mercedes-AMG.

From the GTI to the GT: my path as an engineer.

A portrait of Christian Enderle, Head of Engine and Powertrain Development at Mercedes-AMG.
Text: Christian Enderle
  • From the GTI to the GT: my path as an engineer.

  • Christian Enderle has been Head of Engine and Powertrain Development at Mercedes-AMG since 2012.

    My path as an engineer.

    If you grow up in the Ruhr area as I did, sooner or later you automatically start thinking about cars and how they are powered. I’m not really sure if that’s because of all the motorways that join the cities or maybe the industrial locations and the proximity to car manufacturing plants. Nowadays we could not imagine life without cars – and that is why it was part of my childhood and something I was interested in from early on. When I was young, I used to tinker with anything that had four wheels – and do things to the exhaust system too: because back then “loud” was synonymous with “fast”. I was pretty proud of my Mk1 Golf GTI with a top speed of 180 km/h, which was really fast back in the 70s.

    From tank driver to engineer.

    After I left school with my “Abitur” certificate and before I started studying engineering, I did military service: in the army I was trained to be a tank driver and I naturally worked on the technology of those heavy vehicles. After that time, it became quite clear to me that I wanted to work with vehicles. That is why, after my military service, I went to Aachen Technical University where they offered a wide range of engineering courses. And so, in 1978 I started to study Mechanical Engineering, as the basis of my engineering studies. Out of a choice of eight specialities (including for example textile and production technology) I chose Combustion Engines and Production Technology and I found my personal guru at the “VKA”, the Institute for Internal Combustion Engines: Professor Pischinger, who is very well known in specialist circles.

    A portrait of Christian Enderle.

    Back then, Pischinger taught me a lot about the fine detail behind engines, and as a scientist he had a lot of freedom at the “Institute for Applied Thermodynamics”. I learned from him that a “superior” engine has to have more than four cylinders.

    A fascination for engines.

    The more I learned, the more fascinated I became, because: from an engineering point of view, engines are an ideal and fascinating field for developing new ideas. Creativity is really called for here – and you have to use the whole range of an engineer’s knowledge. In the 1980s the developers were already working more and more on how to reduce fuel consumption and at the same time increase engine output. Their aim was to make the fuel combustion in the engine more efficient. I thought about the idea of sporty multi-valve engines with at least four valves per cylinder. Or would five valves be better? Combined with electromagnetic controls? And what about direct fuel injection?

    From an engineer's point of view, engines are an ideal and fascinating field for developing new ideas.

    More easily said than done: because in those days, the durability of engines was a drawback. We learned from our technical mistakes and then redesigned things. Nowadays, the technical process for engines is far faster and more efficient thanks to specific testing and the fact that you can simulate almost everything beforehand.

    After writing his dissertation, Christian Enderle began working in engine development at Mercedes-Benz.

    Dissertation: direct injection diesel engines.

    When I finished my degree, I wrote my dissertation at Mercedes-Benz. The subject was: “The direct injection diesel engine with a sensational injection pressure of 2,000 bar”. To my great joy, I was then allowed to start working in diesel engine development immediately afterwards.

    When I started, Mercedes-Benz was just considerably enlarging its engine pre-development – so engineers were in high demand, and the company was highly innovative. It was a great time, particularly for a beginner! And eventually, multi-valve engines and direct injection went into series production – which was a small success for me too.

    Christian Enderle discovered his love of cars in his early childhood.

    Becoming the Head of Engine Development overnight.

    Now I want to jump ahead to 2012, when I received a phone call that took me to AMG. The person at the other end of the phone was Ola Källenius, then boss of AMG – he asked me if I could imagine being head of engine and drive train development for AMG. He only let me sleep on the question for one night. That night, of course I had many thoughts: I did not know what was awaiting me in that job – but the fascination of AMG swept all my qualms away. I said yes! I had only just arrived at AMG when I had to take on the first exciting project: AMG was also working on a very innovative family of V8 engines – the M177/M178, which are now fitted in the AMG GT with dry-sump lubrication and in the new C 63 with a wet sump. It was a great opportunity for me, being in on this exciting development right from the start!

    Creative spirit in Affalterbach.

    When we develop a new AMG engine like the M177/M178, we first look at its predecessors and analyse their properties. But of course, we look left and right too: what are the other manufacturers doing, and what is the competition capable of? We are clear about one thing: AMG has to be technically at the forefront; nothing else is acceptable. We always search for a solution that is even better, even faster, even more efficient; and we are not content with the status quo – that is the principal aspect of working with the AMG development team. In the team, we also decide what the new assembly should be capable of, and be able to do better than its predecessor. Sustainability is extremely important for us – but it is also a challenge for our engineers. Together we discuss how we can make a new engine even more efficient and the fuel consumption even lower.

    The AMG development engineers are always in search of better, faster and more efficient solutions.

    And we are successful in what we do: the C 63 manages the NEDC cycle with 8.2 litres of fuel per 100 km – that's an absolutely top figure in this segment, and for us developers that is a small victory we can be proud of. But getting to this point means a very long journey and there are setbacks to overcome on the way. However, the simulation that can be done today, and all the digital tools that are available now help us develop components for engines – these are all opportunities I could only dream about when I was a student!

    Engine sound: the icing on the cake at AMG.

    Nowadays, we can simulate the possible result in the design phase, and thus work on the basic design of the engine and its output data. I am particularly pleased if I can inspire young engineers with my enthusiasm: who knows what the next generation of engine designers will come up with. Perhaps something that is completely new both for Mercedes-Benz and AMG – it doesn’t just have to be five valves per cylinder. The AMG engine sound is part of the specified requirements for every model: each AMG has to produce that unmistakable, sonorous engine sound that still gives us development engineers goose bumps, even though we work on vehicles every day. But as regards sound, there are a number of legal rules and regulations we have to comply with, and they are part of the basic framework for our “sound engineering”.

    Every AMG has to create an unmistakable, sonorous engine sound. Guaranteed to produce goose bumps.

    But we do not want any artificial sources of sound. The engine should produce the sound “naturally”, and really sound like that. That is why we create the AMG sound by using up to three valves, a combination of the exhaust system and its basic layout, and of course the engine itself. What finally decides it, though, is gut feeling: just like composing a piece of music, it's the human ear that finally decides when the sound fits the car.

    From an engineer's point of view, engines are an ideal and fascinating field for developing new ideas.

    The “hot inside V”.

    The M177 4.0 litre twin-turbo V8 engine for the AMG C 63 is a close relative of the M178, the sports car heart of the new Mercedes-AMG GT. Both engines have a twin-turbocharger which is not mounted on the outside of the cylinder banks, but inside the V configuration – experts call it a “hot inside V”. This has advantages: compact engine design, optimum response and low exhaust emissions. Piezo direct petrol injection is responsible for the mixture. I dreamed about that as a young engineer 30 years ago. The 4.0 litre twin-turbo V8 engine complies with the Euro 6 exhaust gas standard, including the ruling on maximum particulate emissions which will come into effect in 2016 – so “clean” and “sporty” are no longer a contradiction in terms!

    Important detail: dynamic engine bearings.

    Another important detail for me is dynamic engine bearings: the new C 63 S and the Mercedes-AMG GT S have them. They solve that ancient technical conflict between the two aims of comfort and driving dynamics by reducing vibrations in the engine/transmission unit. The dynamic bearings can adapt their rigidity – infinitely and at lightning speed – to the prevailing driving conditions and the handling. Softer engine bearings improve comfort by uncoupling noises and vibrations. Handling and agility, on the other hand, benefit from generally stiffer bearings. For dynamic driving, the driver feels closer to the vehicle and gets more response, and the steering response is more direct, too.

    Mercedes-AMG in Affalterbach.

    All in all, the driver benefits from a more precise driving feeling: because the movement of the assembly mass is reduced, the driver has to correct less when steering. I think we can be truly proud of these two (engine) brothers!