The Porsche Turbo: an engineering masterpiece

A famous racing driver from the past, noted for his press-on, full-opposite-lock style of driving, came into our local hostelry the other day, downed a large Scotch and said “Keee-rist”. He had just come down from London in a 3-litre turbocharged Porsche, and having just spent a week with one I now see what he meant. I never thought the day would come when Ferraris, Maseratis, Lamborghinis and similar exotica would pale into insignificance in my book of motoring, but that day came with the Porsche Turbo. If you get the impression that I was really turned on by the Porsche, you are absolutely correct; in fact, the last time a fast car impressed me as much was the Ford GT40.

The car that was loaned to me by Porsche Cars Great Britain Ltd. was the prestige model that was the centre-piece on the Porsche stand at the Earls Court Motor Show, in white with Martini Racing stripes down the sides, red, white and blue special leather seats and red and blue interior, the car being complete with air-conditioning. As it stood there oil the Show stand the price was 1:21,162 and when I went to collect it from Isleworth, after it had been run-in, I found it hard to accept that a Porsche could he worth over £20,000. However, when I returned it a week later I had changed my mind completely, convinced that Porsche were offering £20,000-worth of performance, engineering, quality and, above all else, integrity in all things, which was most heart-warming in these days of the spurious, the artificial, the shoddy and the plain nasty.

When talking to Porsche factory peoples or for that matter their agents, you are very conscious that they all believe in Porsche implicitly, as well they might, and that Dr. Ferry Porsche, and his illustrious father before him, are revered by one and all. Not in the rather mystical way that Enzo Ferrari is revered by Ferrari owners, or Ettore Bugatti was in his day, but in a solid and sound engineering sense, an admiration for a way of doing things and a way of thinking. A few years ago I visited the Porsche Engineering Research and Development establishment at Weissach and came away stunned by it all. In any one department there seemed to be more qualified engineers than there are in total in the world of Formula One, for example, while each department or research subject was utilising equipment that would have paid for a complete Formula One team. It was impossible to accept that the output of Porsche cars could justify such a vast establishment, and of course it was true, Porsche Engineering are involved in many more things than cars, some for outside branches of engineering, some for other car manufacturers and much for the German Government. However, the whole establishment is there and available for any Porsche project, and at the time of my visit the turbo-charged 917 Can-Am Porsche had just been released, after some pretty intensive work on the 4 1/2-litre flat-12-cylinder 917 engine, raising its capacity to 5 litres and its output from 500 b.h.p. to something like 1,000 b.h.p. Since that day I have often mused to myself : “… I wonder what all those chaps at Weissach are up to. . . .” In racing we have seen what they have been up to, with the success of the turbo-Porsches in Group 5 and Group 6 racing, and now I have been able to sample what they have been up to in the form of the production turbo-Porsche. When the Engineering faction at Porsche produced the turbocharged 3-litre Porsche as a production model, the Sales faction reeled back saying they couldn’t possibly sell it, it was just too much of everything and the World could not afford such perfection. They were quite wrong, for the first 500 cars sold themselves and a second production run was soon under way.

The six-cylinder 911 series Porsche has been with us for more than ten years and it says much for the original conception that today’s Porsches are basically the same. The flat-six air-cooled engine has been progressively enlarged, from 2 litres to 2.2 litres, then to 2.4 litres and 2.7 litres, and now to the full 3 litres, without taking up any more space in the car. The two-door fast-back coupe body form has likewise retained its basic shape, flared wheel arches and aerodynamic aids being the main changes in outward appearance, while wheel rims and tyres have grown enormously, following the development in racing. For the driver the Porsche engineers still consider the r.p.m. meter to be the most important instrument and though the steering wheel has been changed many times, now being a padded “safety” affair, when you get into the driving seat the very large 8,000r.p.m. tachometer is the first thing you still see, and it is not an ornamental gimmick, it is a clear and lucid indicator of engine speed. In the lower half is a fascinating little extra dial, reading to 1.5 bar, set into the rev-counter the way some manufacturers used to put a clock in the rev-counter. This gauge registers boost pressure in atmospheres. On the left of the rev-counter are gauges for fuel contents, oil contents in the dry-sump tank, oil temperature and oil pressure. On the right is a 0-150-m.p.h. speedo and a clock. On the left of the steering column is a stalk f°rh lights and on the right a stalk for the wipers. The central gear-lever controls a four-speed gearbox, five speeds being unnecessary with the torque of the turbo-charged engine, as I found out, and all you have to do to start the engine is turn the ignition key; there is no choke or mixture control, all that sort of thing is done electrically within the fuel-injection system. Between the seats is a hand-throttle, and all you get from the engine compartment at the back is a subdued rustling noise, there is none of the whirring and churning you used Lo get with the earlier smaller-engined 911 Porsches.

A blip on the throttle produces little effect, the revs rise but no boost pressure shows, for the system has an automatic by-pass system which operates under no-load conditions. The exhaust gases from the two banks of cylinders are brought together on the left of the engine and pass into a small turbine and then exhaust into a large silencer. This turbine is coupled to a compressor which draws air from a filter on top of the engine, through a mixture control unit and then blows this into the inlet manifold to join the petrol being injected on a continuous pressure system. The no-load by-pass valve exhausts the hot gases from the exhaust collector system directly into the silencer, which is why you get no boost reading when revving the engine in neutral. As you drive off and put a load on the engine the by-pass valve closes, the exhaust gases whirl the turbine round, which in turn spins the compressor and your normally-aspirated engine becomes supercharged and then things start happening. The needle on that fascinating little dial within the rev-counter starts to move when you get to about 3,500 r.p.m., and when it reaches 0.5 you just have time to notice it, before it is reading 0.9 bar and the engine revs are well over 6,000 r.p.m. and soaring. The little turbine spins at a phenomenal 90,000 r.p.m. and the compressor gives 12 lb./sq. in. boost, which produces 260 horsepower DIN from the 3-litre engine. An unsupercharged 3-litre Porsche has pretty impressive acceleration, but when the boost comes in it is electrifying. There is no sudden surge of power or kick in the back, merely an ever-increasing pressure on the back of the seat and all without increase in noise level or any feeling of fuss or strain. The smoothness and quietness is uncanny and you appreciate why the rev-counter is the most prominent instrument; without it you would have no idea of what speed the engine was turning at. Maximum r.p.m. are 6,800, but maximum engine power is developed at 5,500 r.p.m., while maximum torque is at 4,000 r.p.m. The straight-line performance of this Porsche-turbo is almost more than one is prepared to unleash on the open road indeed, I used all its acceleration in 1st, 2nd and 3rd gears, reaching 117 m.p.h. in 3rd at 6,000 r.p.m. and full boost, and felt that the continuing acceleration in 4th gear from that point was almost more than I wanted to cope with, and that is the first car that has given me that feeling on the road.

A friend summed up the acceleration when he likened it to being driven by an enormous electric motor with your right foot operating a rheostat. This feeling is enhanced by the incredible smoothness of the engine, the absence of any mechanical noise or exhaust noise and the very low wind noise of the body. Porsche list the maximum speed as “over 250 k.p.h. (155 m.p.h.)” but I had no opportunity to explore it beyond 135 m.p.h.; however, you don’t quibble with figures given by Porsche, they are those sort of people at Zuffenhausen. To worry about what the cruising speed of the turbo-Porsche is seems pointless, for it will cruise at anything that road conditions will allow, and whether it is running at 3,000 r.p.m. with no boost or 5,000 r.p.m. with 0.5 boost it feels the same and never gives any feeling of being stressed. In the technical specification the fuel consumption is quoted at 15.5 to 19.0 m.p.g., obviously dependent on how much boost you use and what sort of speeds you cruise at, and on one run over a fair distance at an unbelievable average speed a very accurate fuel check came out at 17.0 m.p.g. As I said, Porsche are serious-minded people.

Porsche have not been racing and developing the 911 series cars all this time without Learning something, and the ride and handling are everything you would expect. The Pirelli Cinturato P7 tyres are 205/55 VR16 on the front and 225/50 VR16 on the rear, and that means that there is 7 in. of tread width in contact with the road on the rear ones when stationary, with an inch shoulder each side, giving 9 in. of rubber in contact on acceleration or cornering. It is more than adequate for all purposes for road use. The steering is truly superb, having perfect “feed-back” to let you know what is going on at the front wheels, and while you can provoke the front end to break away, under all normal fast motoring conditions the balance of the car is very neutral. With different size tyres front and rear, you may be wondering about a spare wheel. In the nose of the car is a small-section “get-you-home” spare wheel in a deflated condition that sits under the luggage compartment. Now an amusing game with Porsche staff is to try and catch them out; you don’t often win, for, as they say, “Dr. Porsche thinks of everything.” Seeing the deflated spare tyre I remarked that wouldn’t be amused at having to pump it up. “You don’t have to,” was the reply, “here is an electric compressor which you plug into the cigar-lighter socket and it pumps the tyre up for you.” Looking at the size of the spare wheel compartment I suggested that a punctured rear tyre would not fit into the space. “No,” came the reply, “your girlfriend nurses it on her lap.” I was about to say how much she would enjoy that on a wet and muddy night, when the answer came, “You put the punctured wheel in this plastic bag, and here are some plastic gloves to keep your hands clean while you do so, everything is here in the spare wheel compartment.” Having personally had but two punctures in over 200,000 miles of Jaguar motoring, I wondered if it was all really necessary on the Porsche. “You never know,” came the reply. My favourite Porsche story is of the friend who was talking with some Porsche engineers at the factory and innocently asked if they would ever go into Formula One racing.

Their eyes diffused as they looked towards Munich and they said: “Only if vee half to.”

Obviously the power unit is the most intriguing part of the Porsche Turbo, but almost any other aspect of the car is equally intriguing, fundamental and sound. There is an electrically-operated sunshine roof, with a spring-loaded spoiler at the leading edge that pops up as you open the roof. If the power supply fails you have a small handle in the glove compartment that fits into a socket under a zip fastener in the roof lining and you can wind the roof shut mechanically. In front of the headlamps are high-pressure water squirts, that only operate when the lights are on, and these are fed from a 2-gallon water reservoir in the nose. This reservoir is filled through a filler alongside the petrol filler cap, under a hinged flap in the left front wing. There is no fear of the petrol pump attendant filling your water bottle with petrol. for the orifice will not take the standard petrol pump nozzle. The windscreen wiper washers are fed from the same reservoir and the wipers themselves have three speeds. If you pull the wiper stalk towards you there is a squirt of water and four strokes of the wiper arms. An electric switch operates a continuous water squirt. A large push-pull knob has two positions for sidelights and headlights, and rotating it works a rheostat on the instrument lighting. The steering-column stalk operates fore-and-aft, the central position being dipped, headlamps; push it away and you get full beam, pull it towards you and you flash full beam, so whichever way you flick the lever you get more light. You always get the feeling that Porsche cars are actually driven and used by the engineers at the factory. The pedals are another example; there is no need to double-declutch with the Porsche baulk-ring synchromesh, but from habit I usually do, and I found a toe-heel movement on the brake and accelerator was achieved without Conscious thought, the pedals are in exactly the right places. The brakes are deceptive, for when you first use them the pedal pressure seems high, but when you are slowing daw° from high speed the “feel” is absolutely right and the ventilated discs really knock the speed off. Until you manoeuvre the car in a garage. you are not aware that the steering wheel run is mounted eccentric to the hub, being biased above the centre-line. This is to avoid the solid centre-piece, which blows the horn incidentally, from obscuring the instruments under normal motoring movements. If you never did some rapid twirling movements, while parking for example, I doubt whether you would ever notice this eccentricity. No longer can thieves steal your Porsche by slipping a length of wire between the glass and the rubber seal on a door and hooking the door lock free. To lock the doors you rotate a sunken knurled knob, which retracts the door-locking button down flush with the sill. The internal heating is all controlled by a rotating knob between the seats, on which you dial whatever temperature you require and an electronic device does the rest, with a sensor at the top of the screen and another in the rear that keeps central-control informed of what is happening. The old bug-bear of heaters from air-cooled engines, in which the faster you went the hotter you got and vice versa, is a thing of the past with Porsche. In readiness for another beat-wave a refrigeration plant is an optional extra, though it is referred to as an air-conditioner. There are heating elements let into the rear window and into the lower portion of the windscreen, controllable separately, and a heating element in the outside rear-view mirror. This mirror is in a rather large and ungainly binnacle on the side of the driver’s door and is adjustable electrically by a control on the door sill. The radio aerial is in the right front wing and erects itself noiselessly when the radio is switched on, a change from some that whirr away and clonk into position. Naturally this car has as standard the ultimate in stereo radio equipment, the Blaupunkt Berlin. As with all 911-based models there are two small seats behind the driver and passenger, or the space can he used for luggage to supplement the compartment in the nose. This boot lid, the engine compartment lid and the petrol filler flap are all operated from within the car.

Aerodynamically the car has an air-dam under the front bumper and a flat tray-like spoiler with a rubber lip at the rear. These were evolved from wind-tunnel testing and the sad part is that the most effective rear spoiler, which gave the best stability results consequent with efficiency, was not acceptable to the German law-makers. In his excellent book on the development of the 911 Porsche, Paul Frere explains all this in great detail, With all the test results and information from the Research Centre at Weissach, and rightly castigates the German law-makers for hindering Porsche in their quest to make safe and efficient cars. Porsche’s whole view on safety is that it should be primary, but the average safety-conscious law-maker is Prepared to allow bad cars to be made and tries to legislate for them to be safe when crashed. Porsche’s dictum is that they try and make cars that are fundamentally safe so that they don’t have accidents. There are not many books that I recommend buying, but the 911 Porsche Development by Paul Frere is one of them. If you haven’t already got. respect and admiration for Porsche engineering, it will give it to you. I now understand, why, when asked what he thought was the best car in production today, Frere answered instantly, “the Porsche Turbo.”

As I remarked earlier, when I first got into the Porsche Turbo I wondered how it could represent £20,000, but when I gave it back I only wished I had £20,000 to buy one, for it is a car I could live with. Apart from all the sound engineering you get for your £20,000 you are given a one-year mechanical guarantee with no mileage limit and a sixyear guarantee against rusting out of the main chassis pontoon assembly. The engine only requires servicing every 12,000 miles, such is the perfection that is designed into the Porsche Turbo. These are the quality standards to which Porsche engineering work when building what must be the ultimate motor car. The sports car is not dead, it’s alive and well and being built in Stuttgart.