Birth of the 911…
Updated: Jan 2, 2021
A STAR IS BORN
2021 marks 58 years since the launch of Porsche’s all-new 911 back in 1963, but the real story begins way before then. The story of a legend, from prototype to production
Words: Keith Seume
Photos: Porsche Archiv and KS archives
How do you follow a masterpiece? That was the question on everyone’s lips at Porsche in the late 1950s. The venerable 356 had been around for almost a decade and, despite several revisions, it was clearly not going to go on forever. Porsche had always been a forward-looking company – and now more than ever was the time to start looking towards the future.
The 356 had evolved throughout the 1950s from a largely VW-based sports car into a finely-honed machine which could hold its own on road and track. Or could it? Already there were faster cars on the market, and from some quite unlikely sources. The big Jaguar saloons, with their race-proven straight-six engines, were quicker than a 356 in almost every respect, while even the ageing XK sports cars could show the German coupé a clean pair of heels.
Much of Porsche’s recent development work had been concentrated on the racing line, with the 550 Spyder and 718 RSK stealing the limelight with their race victories. From the outsider’s point of view, it looked like time was standing still as far as the 356 was concerned. It wasn’t, of course, but there was no denying it was time for a change. Time for a new Porsche…
One of the major criticisms of the 356 had been its lack of cabin space. Despite the presence of two vestigial rear seats, nobody could pretend it was anything other than a two-seater with extra luggage space behind the front seats. This clearly limited its market appeal. Discussions at Porsche centred on the possibility of building a true four-seater, a development of the 356 and powered by the same rear-mounted four-cylinder engine.
There had already been some experimentation with ways to ‘improve’ the 356, including the construction of a couple of ‘mules’ which were built up using the front suspension from a Mercedes in one case, and another with strut-type suspension, which closely resembled the design ultimately used on the 911 some eight years later. Featuring longitudinal torsion bars, the system was similar to that used at the rear of the Type 804 Grand Prix car.
Ferry Porsche gave the go-ahead for the new design program in 1959, with the title ‘Type 695’. The technical side of the project fell under the control of Klaus von Rücker, with the small matter of styling placed in the hands of Ferdinand Alexander ‘Butzi’ Porsche. Ideas had already circulated as early as 1957 on how a successor to the 356 might look. Submissions came from a number of outside sources, including Albrecht Goertz in the USA (who designed the VW-Porsche 914) and Pininfarina in Italy, but each was rejected in favour of in-house designs. Butzi Porsche began work on the Type 695 in the latter part of 1959, with early drawings leading to a small wood and Plasticene model in October that year, followed by a full-sized clay mock-up in December.
The result was quite unlike all that had gone before at Stuttgart. Based on a wheelbase of 94.5ins – identical to two four-seat Type 530 prototypes of 1952 – the clay mock-up had a slightly futuristic air about it, especially when compared with the classic lines of the 356. The beauty of working in clay is that it was possible to investigate several different body designs, often two at a time, with one side of the model being finished one way, the other side another.
Front-end treatments varied widely, ranging from Goertz’s American-looking twin headlights to streamlined units that blended seamlessly into the front wings. An integrated front bumper was part of most early designs, both with and without over-riders. At the rear, possibilities included both ‘fastback’ and ‘notchback’ designs, and with one, two or even three tail lights on each side. It is fair to say that none of these early ideas looked particularly pleasing to the eye.
‘He has taste, but he’s not a stylist…’ were the words used by Butzi Porsche to describe his father’s input into the Type 695. But it was Ferry Porsche who would finally put his foot down and determine that the new car should be a 2+2, not a full four-seater. The body design, which was now referred to as the T-7 (all Porsche body styles were referred to by their ‘T’ number, the 356 then on sale being the T-5, soon to be replaced by the T-6), began to mature under Butzi’s guidance.
A non-running, mock-up was built in 1960, with full glazing, and with all the appearance of a finished car. It sat on 356 wheels, but they were about the only reference to the past. Even at this stage, several detail modifications were carried out, with changes made to the front bumper and turn signals, and to the contours of the car’s flanks. On the whole, though, the Type 695 bore a striking resemblance to the final design in several key areas.
By 1961, the Type 695 had matured into a fully-functional prototype that retained the T-7 styling, called the Type 754. At this time no decision had been made regarding the powertrain, so various engines were envisaged, including the current pushrod and four-cam engines used in the contemporary 356.
The Type 754 now had a full interior, with a dashboard that featured a pair of instrument binnacles ahead of the 356-inspired front seats. A pair of smaller folding seats was used in the rear, offering accommodation for two, albeit small, adults or extra luggage space as required.
The T-7 body design was attractive enough and certainly satisfied any notion the company may have had of building a ‘family’ coupé, but Ferry Porsche is reported to have said that there was considerable friction in the design studio between Erwin Komenda and Butzi Porsche.
Komenda had worked alongside Ferry and Ferdinand Porsche since the earliest days. But while he was keen to satisfy the desire of the marketing department to create a four-seat Porsche, Butzi was more inclined to build ‘yet another’ sports car. Komenda’s role was primarily to take care of ‘body engineering’ and it was he, therefore, who was ultimately charged with turning a design into reality.
It is impossible to underestimate the importance of Komenda in the design process of the 911 – his contribution has frequently been overlooked and even Porsche itself has been accused of sidelining Komenda. He was largely responsible for the styling of the 356 and played a major role in the studio prior to the arrival of Butzi Porsche. Sadly, his name rarely appears in connection with the 911.
The T-7 was an interesting design. The waistline was high and flowed in one single line from the headlights back to the tail end of the rear wings. This was a vital design statement that said ‘Porsche’, and had been a characteristic of the 356 from the very beginning. Above the waistline, however, things were very different. The light and airy ‘greenhouse’ featured slim A- and C-pillars, with a B-pillar that sloped forwards from the door shut line. The problem here was that access to the rear seats became rather restricted.
Under the skin, the working prototype was built on the modified chassis of a 356, but with the strut-type front suspension then under development. The Type 754 was ready for testing by Christmas 1961, but there remained the matter of what engine to use. Ferry Porsche, although impressed by the performance of the 356 Carrera, felt that its four-cam engine was too noisy and too costly to consider. The 130bhp output, though, matched his demands for performance, so a Type 587/1 four-cam engine was temporarily installed. Other units that were considered included a fuel-injected version of the 356’s venerable Type 616 pushrod engine, but this was rejected on the grounds that it lacked refinement and sufficient power.
Before the new model could be considered anything like ready for production, the thorny problem of the engine had to be resolved, leading technical director Klaus von Rücker and his fellow engineers to examine other more radical possibilities. To achieve the level of refinement required, there were two options: a six-cylinder engine or an ‘eight’. Porsche was already looking into the latter as part of its racing program, with the Type 753, and later Type 771, flat-eight units under development.
But the general feeling was that an eight-cylinder engine would be too complex for volume production, so those ideas were dropped in favour of a less complicated flat-six. To meet the desired 130bhp benchmark, a two-litre unit was deemed necessary, and would probably lend itself to future development through increasing the capacity and, therefore, power output.
The new engine was referred to internally as the Type 745 and was designed from the outset with a capacity of 1991cc, achieved with a bore and stroke of 80mm x 66mm (these figures are identical to those of the production two-litre engines, which remained in use until 1969). At least two different layouts were investigated before a final decision was made on the engine’s configuration.
The first never made it off the drawing board (see above). It was an unusual design that featured two camshafts mounted below the crankshaft, one for each bank of cylinders. Pushrods and rocker arms were then used to open the valves. The second was equally as unusual, with, again, two camshafts, this time one above the crankshaft (to operate the inlet valves), the other below (for the exhaust valves). This design actually made it off the drawing board, into the engineering shop and into the back of the running Type 754 prototype.
Cooling was by a pair of axial fans mounted at the front of the engine (rear of the car) driven by belts off the crankshaft, in a similar fashion to the air-cooled Tatra V8s. Two triple-choke carburettors were mounted outboard of the cylinder heads, necessitating a wide engine bay. Also worthy of mention was the lubrication system, which featured a separate oil tank mounted on the engine, alongside the flywheel.
Although the engine functioned well enough, it was very noisy and soon gained the nickname ‘the threshing machine’. Unimpressed, Ferry Porsche decided that from that point forward, his company would never build a pushrod engine again.
There were significant changes afoot. Klaus von Rücker left Porsche early in 1962, to be replaced by Hans Tomala, the upshot of this move being a major technical review of the whole project. The first was clearly a review of engine development, but the second and in many ways the most important was the decision not to pursue the idea of a four-seater Porsche – instead, the new car would be a 2+2 coupé.
The decision to follow this path presented a new problem in that the prototypes had been built around a 94.5in wheelbase, unnecessarily long for a nimble sports car to Ferry’s way of thinking. He acknowledged that the new model needed to be longer than the 356, and after much deliberation, a wheelbase of 87ins was decided upon – some 4.4ins greater than that of the 356.
These two vital decisions – wheelbase and body style – meant a literal return to the drawing board. Butzi Porsche took certain elements of the T-7 body design – most notably virtually the entire front end from the windscreen pillars forward – and adapted them to a shorter coupé profile, which had overtones of the Komenda-designed Cisitalia coupé of 1947. The windscreen was raked back slightly and, to compensate for this, the B-pillar leaned back to aid access. The roof profile was redrawn as one single curve from the top of the windscreen back to the tip of the tail. Thus was born the T-8 body design.
The T-8 is instantly recognisable today as the forerunner of the 901/911 as we know it, but there were still several details that needed to be finalised, such as the air intake grills for the engine’s cooling system. On the final version of the T-7, there were small grills on each side of the car, set low, just ahead of the taillights. This layout was abandoned on the T-8 and several variations on a theme of incorporating intakes in the engine lid were tried, ranging from a pair of 356-style grills, to wide louvres punched into the lid laterally.
The general consensus was that the T-8 design ‘worked’, both aesthetically and practically. What now remained was the small problem of the engine…
The Type 745 design, with its pushrod-operated valve gear, had been rejected. With the departure of von Rücker, there appeared a new name on the team list: Hans Mezger who, up until now, had been working in the race department. He began work on Type 821, another air-cooled flat-six, this time with overhead camshafts driven by chain from the nose of the crankshaft. Other systems had been considered, such as rubber belts (common today but considered ‘unpredictable’ in 1962) and both gear- and shaft-drives. The latter were both rejected on grounds of cost and noise.
Although responsible for the overall design of the new engine, Mezger was aided by a certain Ferdinand Piëch, nephew of Ferdinand Porsche and an experienced engineer, with an eye for detail. Between them, they saw the Type 821 through to a running prototype unit, which was very similar to the design of the final production engine, with one major exception: it featured a ‘wet-sump’ lubrication system. Cooling was now taken care of by a single belt-driven fan, which on the first test engines had 17 blades, later reduced to 11.
Early in January 1963, the designation ‘901’ first appeared in writing in reference to the new car, and the development engine was referred to as the ‘901 engine’ from October that year – a month after the first public viewing of the car at Frankfurt. Engine development continued, though, and the Type 821 design was further refined by the addition of extra main bearings (there were now seven within the crankcase, plus an extra support bearing at the nose of the crankshaft), along with the use of a dry-sump oiling system with a remote oil tank.
There were a number of advantages to this, among them being a reduction in overall height of the engine and an increase in the oil capacity – useful when the circulating oil helps cool the engine almost as much as the passage of air over the cylinders. A dry-sump system also solved any problems caused by oil surge under hard cornering.
The final production-ready version of the engine produced 130bhp from its 1991cc displacement and was a technological triumph in every respect. Running triple-choke Solex ‘overflow’ carburettors, feeding through a steel air-box mounted across the top of the engine, it was a tribute to Mezger’s and Piëch’s engineering know-how.
But what of the remainder of the 901’s underpinnings? The design of the front suspension had been finalised, with welded steel lower wishbones pivoting at their inner ends on longitudinal torsion bars, while vertical damper units served the same function as a McPherson strut, minus the coil spring. It was an ingenious design, which allowed the fuel tank to be mounted low within the car, unlike the transverse torsion bar set-up on the old 356.
In a throw back to the ‘old days’, a swing-axle rear suspension layout had been a feature of the running prototypes right up until early 1963. However, shortly before the 901 was signed off for production, that was all changed in favour of the ‘four-joint’ design that is still favoured today. Semi-trailing arms and longitudinal spring-plates formed ‘trailing wishbones’ on each side of the car, with articulated driveshafts attached at their i
nner ends to a five-speed transaxle unit. Porsche’s beloved torsion bars again served as the springing medium, this time with two of them – one each side – mounted transversely and acting as the front pivot point for the spring-plates.
The transmission itself was an all-new design, developed jointly for the 904 Carrera GTS competition car and the road-going 901. The link with the 904 is largely the reason why the 901’s five-speed gearbox featured a ‘dog-leg’ first gear, selected by pulling the lever hard over to the left and back. Second gear was located forward and to the right of reverse (which was directly opposite first gear…), forming part of a conventional H-pattern layout for the top four ratios.
The main reason why the dog-leg arrangement found favour was because, in racing, it was felt that the ability to select first gear swiftly was of little importance. First gear was generally selected at rest and used solely to get the car underway – it was thought to be more important to be able to shift between the other ratios with the minimum of fuss. Of course, the dog-leg layout worked well when there was no wear in the gear linkage – and when used on a left-hand drive car. Drivers of RHD cars that required shifting with the left hand found the arrangement somewhat less satisfying – and worn a linkage often led to missed first–second gear shifts…
The 901 was first shown to the public 50 years ago at the Frankfurt show in September 1963, four busy years since the Type 695 project had been given the go-ahead by Ferry Porsche. In development terms, that is remarkably quick – but there was still another year’s work ahead before Porsche’s new baby was ready for sale to the public, with a great deal of attention being paid to interior trim, engine cooling system and minor body detailing. It was worth the wait…
First published in 911 & Porsche World magazine, April 2013