The Porsche 928
A Car for the Eighties
Even under the accumulated mud of a couple of thousand miles spent in a round-Britain pursuit of the RAC Rally the Porsche 928 is a striking car, its bullet shape, futuristic wheels and vacuum-operated headlights pointing naked to the sky often attracting more enthusiastic gapers than the cream of the world's rally cars whenever our manual gearbox test car was parked nearby. It is that kind of attention afforded to the appropriately registered 928 JRR that will make many owners shell out £20,498. But it is not extrovert prestige value that has caused the 928 to receive universal acclaim, including the 1978 Car of the Year Award. This all-new 4½-litre, V8 Porsche is full of innovative engineering and equipment which is not mere gimmickry but functional and anticipatory. It is a fascinating package.
I described the 928 in detail in Motor Sport, May 1977, after driving a left-hand-drive manual version in Germany. Brief acquaintance with a car is one thing; to live with it - and I even slept in it during those 2,000 miles packed into five days of the RAC tells much more. D. S. J. borrowed the manual car for a couple of days too and subsequently he, W. B. and I tried the automatic version pictured here. Thus the following is a mixture of impressions. Both gearbox options cost the same in the UK, while the overall specification is such that extras can be discounted.
On the whole we were not disappointed with this interesting new generation Porsche, but that is not to say that it is the ultimate "supercar", for it is not totally free from snags and is beaten on individual counts by several competitors. It does not have the velvet-gloved, well-nigh silent progress and comfortable ride of the £5,300 cheaper Jaguar XJ-S, for instance, nor the shattering performance of the Aston Martin V8 at £22,999 to £23,999 or especially the Vantage at £25,999. What it does have is a chassis with such incredibly good roadholding that it actually takes some of the fun out of driving. And there's a sad state of affairs. It has a power producer under the bonnet which is so amazingly efficient that it could be an electric motor or a steam engine, although in terms of sheer performance this 928 is only on the fringes of the "supercar" category. Just about the only thing shared with the 911 series, other than the steering column switches and the Turbo steering wheel, is that overall feel of engineering integrity, the sensation that every detail has been designed as the best and most efficient solution, not the easiest and cheapest. And that is what real Porsche motoring, as distinct from 924 Porsche motoring, is all about.
Otherwise the 911 series should be forgotten when thinking about the 928, just as the 356 had to be forgotten when the 911 appeared on the scene. Whereas the 356 and 911 series developed from the influence of old Dr. Ferdinand Porsche carried on by the Zuffenhausen workers, the 928 is the product of Porsche Systems Engineering as Porsche enter races under at Weissach. This is a car for the eighties, anno domini, not m.p.h. nor m.p.g. It is Weissach's solution to sports car motoring in the future, when the safety factions have had their heavy-handed, legislative say and machinery for pure driving pleasure, like the 911, has been outlawed.
Yet the 928 is not intended as a replacement for the 911, which has a few years and probably a more direct substitute ahead of it. Porsche themselves describe this V8, 2 + 2 coupe as three cars in one: "a thoroughbred high-performance sports car, a luxurious coupe, distinguished by its outstanding comfort and refinement, and yet a versatile, economical vehicle designed to provide virtually maintenance-free operation over a long period". On price it fits between the 911 SC (£16,300 in Sports trim) and the 3.3 Turbo, now a hefty £26,250 and reputedly fetching up to £32,000 from those with pockets deep enough to circumvent the two-year waiting list. The waiting list for the 928 is already approaching two years, by the way, and I know of one that has changed hands for £27,000.
Rear engines were out so far as the long-term future was concerned, Porsche decided, and mid-engines posed too many accommodation problems. Their answer was to give the 928 a practical front engine and rear wheel drive layout, but to regularise weight distribution by mounting the engine behind the front axle line and putting the gearbox in unit with the rear axle, joined to the engine by a torque tube. That decision was made before the 924 project began at the behest of VW-Audi. Excepting layout, the 928 shares nothing, not even a body panel, with the 924.
The power house which shifts this 28½ cwt. curvaceous missile so efficiently is a water-cooled, all aluminium, 90 degree V8 of 4,474 c.c, capacity and prominently oversquare bore and stroke dimensions of 95 mm. x 78.9 mm., within which steel or chromium-coated aluminium pistons (varying with supplier) bear directly upon unlinered, aluminium bores.
Toothed belts drive a single overhead camshaft per bank, with hydraulic tappets for ease of maintenance. Bosch K-Jetronic fuel injection is fitted, as is electronic ignition. By Porsche standards this wet-sump engine is lightly tuned, to produce 240 b.h.p. at 5,500 r.p.m. (their 3.3-litre Turbo gives a grand 300 b.h.p.), only 15 b.h.p. more than the 450 series Mercedes engine. What they were after was flexibility, ensured by a gentle torque curve which peaks on 257 lb. ft. at 3,600 r.p.m.
The result is an engine which does not sing more happily the higher the revs., like a Porsche flat-six or any Ferrari engine. It does not run out of breath at the top end, but doesn't give any encouragement to hang on to the revs. With all that torque there is simply no need to use all the available 6,000 r.p.m. and on neither manual nor automatic cars did I bother to test whether the 6,300 r.p.m. ignition cut-out was operative. The five speeds of the manual box are largely unnecessary. D. S. J. was moved to comment that three speeds would be adequate. Had he "hammered" the 928 across the twisting, narrow and slippery moorland roads of northern England and Scotland in the dead of night he would probably have added an extra gear to his choice for the sake of engine braking, car control and ensuing peace of mind. I would have been very happy with a good four-speed gearbox. If the five-speed gearbox had been pleasant to use I doubt whether either of us would have complained about too many gears, we would simply have missed a few more out across the gate when being lazy. Unfortunately it is not a particularly pleasant gearbox, which makes a bit of a nonsense of Porsche's comment to me last year, while agreeing that five gears were unnecessary, that "we consider a keen driver would want them to improve his enjoyment". The gate is quite wide and places first gear on a dog-leg down to the left, opposite reverse. A detent spring must be overcome to engage either of them, but there is only gentle spring bias into the central second to third gear plane. This notchy gearchange needs thinking about, especially from fourth to third: it is not a "joy" stick like on a Dino or even my Alfa Spider, nor so positive as the similarly gated ZF box on the Aston Martin Vantage. Each gearchange needs thinking about instead of being executed automatically, so the tendency is to rely on torque rather than b.h.p. to avoid moving the lever, which is a bit too far back and too high for shorter drivers. A twin-plate clutch at the engine end of the drive train copes stalwartly with the torque, though with an occasional judder on take-up from rest. It needs to be fully depressed to the end of its long travel. Spring assistance ensures that it is not too heavy.
Although the 928 may not be in the same league on performance as some "supercars" and won't excite the adrenalin in a straight line as much as a Vantage or a Turbo, it remains a very high speed performer. The manual car will reach 60 m.p.h. from rest in just over 7 sec. and 100 m.p.h. comes up in around 18 sec. There is enough power to set the rear tyres smoking in 1st, 2nd and 3rd if a full power take off is attempted on a slightly greasy surface, pound notes curling up in the blue haze from each rear 225/50 VR 16 Pirelli P7; at £180 each, such lead-footed behaviour mustn't become a habit . . .
Speeds in the gears at 6,000 r.p.m. are approximately 45 m.p.h., 65 m.p.h., 90 m.p.h. and 120 m.p.h. One hundred and twenty m.p.h. is an easy cruising speed and the test car happily swung the needle of its electronic speedometer to 142 m.p.h. Porsche claim 143 m.p.h. for the manual car and 140 m.p.h. for the automatic. As D. S. J. remarked, it has enough "get up and go" in fifth at 100 m.p.h. to put it into his short list of fast cars. That long-legged fourth was a very useful gear in RAC country.
Porsche's no-extra-cost alternative to the largely unnecessary five-speed gearbox is an adaptation of the excellent Mercedes-Benz three-speed automatic. As anticipated, this proved to suit the smooth V8 magnificently, giving the 928 a much more refined character. Not much performance is lost through the torque converter - between a second and two seconds between the standing start increments right through the scale and a couple of miles per hour at the top end and there is rarely any need to use the manual hold. Full throttle change up points launch the car up to 60 m.p.h. and nearly 105 m.p.h. in the two lower gears and full kick-down which needs heavy throttle pressure and is prone to lethargy will bring in second at anything up to about 80 m.p.h. Unlike Jaguar with the V12, Porsche are happy to let their V8 kick-down into first on full throttle. The gearbox ratios and settings are ideally suited to the engine, up and down changes are hardly perceptible and this is not one of those automatics which waltzes up and down through its ratios unnecessarily. The T-handle selector is positive to use and has a thumb-button in its end to be depressed for engagement of reverse or park, but there is no stop to prevent the lever being pushed inadvertently from second through drive into neutral, a hazard which is usually encountered on full throttle. D. S. J. and I use left-foot braking on automatics and were disappointed to find the 928's broad brake pedal too offset to the right to use this action comfortably.
The 928 looks a huge, wide car on first approach, but gives little of this feeling when driving it under most road conditions. The sides bulge beyond the window line and out of the driver's vision, but the two door mirrors, each individually adjustable from the driver's door and heated via the two-stage heated rear window switch, protrude beyond the body line to help judgment. The secret of shrinking a car which measures over six feet wide is precision of handling and this, together with roadholding, is really what the 928 is all about as much as performance, price and prestige. Its wide-tracked suspension uses cast aluminium wishbones, an anti-roll bar and coil spring damper units at the front and Weissach's own very special rear axle design. This coil sprung independent rear end has transverse upper links, semi-trailing bottom arms effectively forming wide-based wishbones and an anti-roll bar; its geometry is designed to prevent normal rear wheel steering tendencies caused by toe-out under cornering forces. The crowning glories of this suspension package are those massive, low profile, Pirelli P7s on space-age style 7J alloy wheels.
Attention to weight distribution, even to the extent of mounting the battery on the rear of the transaxle, makes the 928 an inherently well-balanced car. The grip of those broad P7s in the dry is phenomenal and few drivers are likely to find their limits. The natural tendency is towards understeer as speed rises; pushed to its limits on a fast corner all four wheels drift gently. Lifting off the throttle tucks the nose in. It takes a violent throttle application to kick the tail out on a tighter bend and response to correction is instantaneous. One of the 928's finest points is its ZF variable ratio, power-assisted rack and pinion steering, which simply does not feel like power steering, being superbly weighted and nicely geared at just over three turns lock to lock for a remarkably tight turning circle. Its response, particularly on turn-in, via those low profile Pirellis is excellent. Wet weather grip and behaviour is good, though a great deal of respect is required. Better weight distribution and negative scrub front geometry make the 928 far less susceptible to aquaplaning than the 911 series, over which it also has the superiority of good stability in cross-winds.
But the story of the 928's chassis behaviour is not one of total perfection. For a start it is noticeably subject to surface camber changes and alternating rough tarmac; power steering or not, conscious effort is needed to hold it in a straight line and out of the gutter in such conditions. With hundreds of miles of such roads to contend with during the RAC Rally, I frequently had to slow down just to relax tiring arms and shoulders. The reason for these reactions seems to be one of geometry more than the influence of ultra wide tyres. Likewise heavy braking on an uneven surface can provoke quite a bit of twitching from the nose end. Straight line running at three figure speeds is not as good as it ought to be: it is extremely stable, right up to maximum speed, but the driver has to work with the wheel to avoid deviation; it does not have the dart-like high-speed running of an XJ-S for example. Again this seems to be a geometrical problem, though the otherwise perfect steering is less sensitive in the straight ahead position.
Whereas I tend to drive a 911 very quickly all the time just for the fun of it, I sometimes found myself driving the 928 like an old woman; at mid-range speeds it feels to be going faster than it actually is and an overtaking Marina can wake one up and hurt one's ego. Fast main roads are the 928s forte, when roadholding attributes come out best. I found it less satisfactory on twisting roads with difficult-to-read corners, especially on wet and greasy surfaces and really had to will myself to drive quickly when schedule demanded in these conditions. Despite such a sophisticated chassis, the 928 then became something of a point and squirt machine. The limit of adhesion was difficult to judge and the Weissach axle's effectiveness was sometimes an embarrassment; my reaction in most conventional cars to an unexpectedly tightening corner would be to try to throw the tail out to prevent terminal understeer; the 928's rear suspension actually fights against such measures. I found myself braking more and earlier than necessary on these winding roads, using a slow in, fast out technique which seemed to be a waste of those fat tyres.
Those Pirellis are responsible for some other shortcomings. Different tarmacadams orchestrate music varying from rumble to howl from the P7 treads and only a few very smooth surfaces cause them to hush. The stiff side-walls help make for a harsh, sometimes choppy ride and give rise to a lot of bump thump. Thankfully the exceptionally comfortable seats deaden much of the effect. Most of the noise in the 928 is generated by the tyres, for the engine is most subdued at low revs, rising only to a very pleasing, purposeful growl beyond 4,000 r.p.m., while wind noise is low.
The brakes on the manual test car confounded Porsche's claim for "virtually guaranteed fade-free characteristics" on the way up to Donington Park on the second day of the RAC. The reason for the fade became obvious when the brake pad wear warning light came on during the run out to Wales on the fourth day and I had to practically pussyfoot my way round the Principality with stopping power gradually deteriorating. Porsche claim 12,000 miles between services for the 928; the pad warning light first glowed at 10,740 miles. To be fair, 928 JRR had already had a very hard life in the hands of other testers, but it will obviously pay hard-driving owners to check pads between services. The brakes in question are ventilated. discs all round, 11.1 in. diameter at the front, 11.4 in. rear, with fully-floating calipers. They were much more effective on the low-mileage automatic test car, but not so impressive as those of the later 911 series cars.
An essential prelude to climbing in for the first time through the driver's door, aluminium panelled like the front wings, bonnet and hatchback, is to spend an hour or so studying the comprehensive manual. The 928 has so many little tricks tucked away in its cockpit that some will never be found without prompting from the manual. The front occupants sit in padded seclusion from the outside world, a feeling magnified by the curved integration of the door armrests into the facia and the centre console. There's a space-age aura about the design, but traditional craftsmanship in the leather work.
Nearly all the controls are contained in the big instrument binnacle or on the steering column; the binnacle moves with the rake adjustment of the column so that the relationship of switchgear to the driver's hands never changes, nor do the instruments become obstructed by the thick-rimmed, leather-covered wheel. The manual test car arrived with the driver's seat set in the lowest position, too low for comfort, so that I found myself peering over the binnacle, leading to strain and reduced confidence, particularly when the headlights were raised at night. The seat height can be raised by the dealer so a regular driver should not be troubled, I found too large a gap between the notches in the seat slide adjustment so that I was either too far forward or too far back for the long clutch and throttle movements. Electrical seat adjustment, fitted to the car I drove in Germany, will soon be offered on the UK market, and includes height adjustment. I felt much more comfortable and confident in the automatic car, which had the higher seat setting and was less critical on pedal reach. Pedals are curiously arranged in the manual car, the clutch being way over to the left, with a big rest to one side, and throttle and brake way over to the right, calling for splayed legs. In practice, this goes unnoticed. Heeling and toeing is awkward. Former Motor Sport journalist Andrew Marriott, who passengered me and manned the maps during the RAC, and I were full of praise for the form-hugging seats, in which we often spent hours on end. Rear seat room is restricted, but Porsche sell the 928 as a 2 + 2 not a four-seater. Yet my 5 ft. 7 in. frame was comfortable enough for an hour or more in the back whilst D. S. J. sampled the automatic car. The rear seats are separated by a console with lockable-cubby-hole over the trans-axle.
Normal boot space beneath the hatchback lid is not over-generous, but this can be extended considerably by folding down the seat backs together or individually. A net strung between them stops luggage flying through from the boot. The detachable luggage cover provided is a bit cheap and nasty and difficult to clip under the edges of the seat backs. One thing lacking from all the 928s gadgetry is electric locking for the hatchback, something that even the £2,800 Mazda Hatchback boasts.
Instrumentation it exceptionally clear and comprehensive. When the ignition is turned on the binnacle lights up like Blackpool Illuminations, spelling out in English in the left hand dial warnings for low washer fluid, failed tail or stop lamp bulbs, parking lights and coolant. Similarly, in the right hand dial, warnings for brake fluid, brake pad wear, brake "press" (which blinks an failure of one of the dual circuits), parking brake and low engine oil level or pressure. Most of these are linked to a bright central safety warning light cum push-button in the centre console, which comes on in unison with the binnacle warning words in the event of a malfunction. If the malfunction isn't too serious, in the case of my worn brake pads (this errs on the safe side), or low fuel level, for example, the central light can be cancelled, although the binnacle warning remains. If something more serious is amiss, like low oil pressure, the light cannot be extinguished.
The efficient handbrake, which operates on separate drums within the rear discs, lies by the driver's right thigh and was sometimes awkward to release on both test cars. Alongside it are two knobs, one for front/rear speaker balance of the Porsche-Blaupunkt stereo system (a self-seeking device which took more learning to "drive" than the car) and a headlamp beam height adjustment. This very useful vacuum-operated device is meant lo allow for differing loads: I found it most useful for varying terrain, allowing a king beam or closer spread if necessary. Auxiliary spotlights, doubling for daytime flash, operate with the halogen headlights on main beam. I found the lights adequate, but D.S. J. would have preferred even more light. Fog lamps are fitted too. High pressure water jets blast dirt front the headlights.
Air conditioning is standard. I found it preferable to use heated air-conditioned air rather than the normal fresh air heating. Outlets in the doors can be used for side-window demisting or personal heating/cooling. There is even an air-conditioning outlet in the glove locker to protect your Toblerone or make-up in hot weather.
Provision against wet and dirty screens is excellent. A steering column stalk operates three constant speeds for the wiper, or an intermittent wipe, the speed of which can be controlled by a knurled knob under the facia. A push-button alongside directs a timed blast of concentrated cleaning fluid on to the screen, a facility in addition to the normal high-pressure, four-jet screen washers with 8-litre reservoir. A parallelogram wiper looks after the rear screen. Electric windows are fitted.
A Tempostat speed control is standard, controlled by a steering column stalk. The lever is pushed forward to set the speed control at the speed the car is travelling at the time. This can be overridden by the brakes or throttle, but it has a memory which will recall the last set speed if the lever is pulled down. It is cancelled by the ignition. I found this a very useful gadget on motorways during the RAC, setting it at just above the legal limit to avoid the wrath of the police, who were out in force to overlook the Rally's entourage. It makes for lazy driving, but keeps speed uncannily steady.
Other neat details which come to mind are an automatically illuminated vanity mirror tucked away in the headlining behind the sun-visor, two-position armrests in the doors, which double as lids for the deep door pockets, a little torch set into the ignition key and the very tidy toolkit shown in the colour photographs. A space-saver spare wheel and tyre housed below the luggage bay is illegal for use on British roads, pending an appeal by Porsche, who give free membership of the Car Recovery Service Club as a substitute.
One of the major causes for comment about the 928 is the lack of bumper bars. In fact both ends of the car are capped by polyurethane "bumpers" covered in elastic, body-coloured paint. Behind these are "proper" hydraulic strut bumper bars designed to withstand a 5 m,p.h. impact without damage.
By big-engined car standards the 928 is commendably economical of fuel, from which it demands only 91 octane. The manual car recorded a worst of 17.1 m.p.g. and a best of 19.72 and was usually in the mid-18s during those arduous five days. The automatic was thirstier, as expected, recording a worst of 15.18 m.p.g. and best of 15.78 m.p.g. Thus the range is satisfactory from the18.9-gallon, synthetic tank.
The Porsche 928 is an enthralling car, so obviously the result of "thinking" engineers. It is not yet the Perfect Porsche, for it is lacking in respect of ride and noise levels and its much-vaunted chassis behaviour is sometimes suspect in less than perfect conditions, but my goodness, both Jenks and I could live with one. - C. R.