Φέτος συμπληρώνονται 30 χρόνια από τότε που η BMW παρουσίασε την M5, με την εταιρία να μας θυμίζει την τρίτη γενιά της. Η M5 E39 αρχικά ήταν να μην περάσει στη παραγωγή, μιας και η BMW δεν πίστευε και πολύ σε αυτή. Ο Alexander Hildebrandt αναφέρει πως τα μεγάλα κεφάλια της BMW είχαν πάρει την απόφαση να μην κατασκευάσουν την M5 E39, αλλά οι Karlheinz Kalbfell, Carl-Peter Forster και Dr. Wolfgang Reitzle ήταν εκείνοι που αποφάσισαν το μοντέλο να περάσει στη παραγωγή.
Για πολλούς, η καλύτερη γενιά της M5, ήταν να φορέσει έναν εξακύλινδρο εν σειρά κινητήρα, αλλά η ιδέα απορρίφθηκε. Στο τραπέζι έπεσε επίσης και η λύση ενός turbo εξακύλινδρου κινητήρα και ενός ατμοσφαιρικού V8, με την BMW να προτιμά έναν V8 4,9-λίτρων απόδοσης 400 ίππων με 500 Nm ροπής.
How the third BMW M5 was born. An insider remembers.
Part 3 of the series: 30 Years of the BMW M5.
Over the coming days, we will be celebrating 30 years of the BMW M5. Thirty exciting years with five model generations – from the in-line six-cylinder, remembered by many as the engine in the legendary BMW M1 to the V8 M TwinPower Turbo engine of the current BMW M5. Looking back, the third-generation model with its discreet appearance was not always at the forefront of the fans’ attention. This can hardly have been due to the brawny 4.9-litre, 400 bhp, V8 engine, all the more bearing in mind that this design, as was always typical for BMW M, featured an extremely direct response. In its day, 7,000 rpm was more than respectable for such a large-volume V8 engine. Alexander Hildebrandt, Head of Product Marketing BMW Germany.
The developmental history of the third BMW M5 generation is not so well known, but this only serves to make it even more interesting. Alexander Hildebrandt has granted us a look behind the scenes. Today he is head of product marketing at BMW Deutschland, but his twelve years at BMW Motorsport GmbH and BMW M GmbH have left an indelible mark on him. Somewhat tongue-in-cheek, he describes himself as ‘the godfather of the M in the marketing department of BMW Deutschland’. During his time at BMW M, he was head of marketing until 1998 and overall project manager responsible for the BMW M5 (E39).
‘I well remember the discussion surrounding the BMW M5, which in the eyes of the fans was tarnished to a certain extent, at least in the early days.’ He is referring to the V8 engine, which signalled the end of the six-cylinder era of the BMW M5. The fans’ wistfulness was understandable, after all this was the engine that celebrated its premiere in the legendary BMW M1 Premiere, and now its services were about to be dispensed with. But it was no use, the new BMW M5 was going to have to set new standards, and to achieve this, it would need plenty of power under the bonnet. The team at Garching was fully aware of what the BMW M5′ customers wanted. ‘The goal we set ourselves was not inconsiderable: if we were going to build a car like this, it would have to be one that would make its presence felt in terms of its performance. Its engine size would be four-point-something’ remembers Hildebrandt. This was something that the in-line six-cylinder engine of the BMW M1 simply could no longer achieve – the engine design had progressed as far is it could possibly go in terms of engineering.”
“Soon, the V8 would prove to be the only feasible means of fulfilling these performance requirements. Nevertheless, many alternatives were considered as the basic concept for this BMW M5; it had to be both contemporary and would also work out in terms of cost. The ideas ranged from a supercharged six-cylinder to a V8 engine, the latter of course being the design that was ultimately selected. ‘At that time, a bi-turbo would have been uninteresting, especially for the USA, because turbo technology was not yet so highly developed in terms of response and cost effectiveness.’
But time was marching on, and the lifetime of the E39 was advancing inexorably. And so the decision was taken to take BMW’s series eight-cylinder and to toughen it up until it more than met the standards by which fans and customers of BMW M measured themselves. This was an experiment that quickly proved successful, for the engine had considerable potential. ‘First of all, we built a demonstration engine, which already displayed a number of persuasively good characteristics.’ Looking back, the customers confirmed that this had been the right decision: ‘this BMW M5 was the most successful car that we had hitherto brought out onto the market,’ stresses Alexander Hildebrandt. Why was this the case? Because the classically simple exterior concealed a natural sporting talent. Where else could you have got a serial limousine at that time that enabled lateral acceleration forces of 1.2 g?
And yet it could quite easily have worked out so differently: ‘the alternative would have been not to develop the car at all. These were difficult times for large, powerful cars. ‘Indeed, the bosses had actually decided against building this car. But my superior at the time, Karlheinz Kalbfell, was not prepared to take no for an answer.’ Another supporter was Carl-Peter Forster, series manager for the BMW 5. Also in the boat was Dr. Reitzle, who ‘was an M fan anyway and at the time concurrently head of development and sales. He did not take much persuading. In the end, it was his vote that swung the required operational number within the marketing group.’ So the BMW M5 was given a chance. Another major positive influence in support of the BMW M5 was the American market, where the BMW M3 had been launched successfully without the throttle valves typical of BMW M. ‘This meant that America also considered the BMW M5 a potentially successfully idea.’
Nevertheless, the company wanted to be able to offer customers a genuine M car – and the engine was always going to be the centre of attention. ‘Response, spontaneity, power delivery, all of these and more have a defining effect on the character of a BMW M car.’ The biggest challenge was therefore to make an M engine from a recognised, well-performing V8 series engine. ‘There were several problems that were anything but simple to solve, such as the rigidity of the cylinder block, which necessitated two or three development loops.’
But in the end, it was worth all the time and expense, and the V8 engine developed into a splendid performer, which was capable not only of generating 400 bhp but also releasing a beefy torque of 500 Newton meters already at 3,800 rpm. For the first time, electronically controlled throttle valves had been fitted, that could be opened in 120 milliseconds by means of servomotors. The use of double VANOS resulted in an appreciable improvement in response. By activating the Sport button, the signals given through the accelerator pedal were adhered to even more directly. As a result, this BMW M5 managed the intermediate acceleration range of 80 to 120 km/h in only 4.8 seconds.
‘Looking back today,’ remembers Alexander Hildebrandt, ‘the obvious question is how on earth could people have even considered not building what ultimately was to become such a successful BMW M5? Decisions are always made under certain conditions that prevail at a certain time. It is therefore quite legitimate to consider whether to continue doing certain things, or whether to do them differently, or whether to stop doing them.’
But all’s well that ends well: ‘I know some people who still drive this BMW M5 today. This car was a really beautiful and fast travel and sport limousine – which is why it was so successful. Those who have one, love it.’