Porsche's 924: a disappointment
Porsche's radical departure front established air-cooled, rear engine design principles into the field of-water-cooled front engine sports cars with the 924 has done remarkable things to the Zuffenhausen-based company's turnover. Between the 924s introduction in February 1976 and July, orders from Europe and the USA reached a level high enough to justify opening the taps to achieve the maximum production capacity of log cars per day, against about 50 911s. To Porsche this is a measure of the success of their philosophy in producing a down-market model to capture a comparatively less-well-heeled section of the public—customers who covet a 911, but will make do with second best so long as it carries the marque name. The philosophy may well be a success, but if the standard of our recent road test 924 is the measure of engineering design success it is a philosophy which, through the shortcomings of the model, will do much to tarnish a revered name. The 924 is a bit like the curate's egg: good in parts. The parts which are good, especially the handling, are exceptionally good. The parts which are bad, especially the noise, vibration and harshness are, well, bad.
The background to the 924, described in Motor Sport, February 1976, is worth repeating to keep the model in perspective in the context of this road test. Porsche engineers evolved it at their Weissach design and research centre as an outside contract from VW-Audi, who intended to put their badge on it. Hence the largely Audi mass-produced saloon running gear. When Toni Schmuecker replaced Rudolf Leiding as head of Audi-NSU, he decided to kill this projected Audi sports car, which by then was almost ready for production. Porsche considered that the project had gone too far to be shelved, did a deal with Audi to take it over and, presumably much to Audi's delight, arranged to have it manufactured under contract at Audi-NSU's practically bankrupt Neckarsulm plant, where production is supervised by Porsche technicians. Porsche claim that £60 million pounds was put into tho design, production and launch of the 924, but how the intricacies of that finance were interwoven twixt Audi-NSU and Porsche is anybody's guess.
The 924 is almost large enough to be considered as a sports saloon on the lines of the Alfetta GTV rather than a sports car. The all-steel bodywork has simple, yet sleek, rounded lines, following Porsche's proven belief that such a theme is essential to avoid premature ageing in a car designed for a long production run. The two doors are wide to facilitate access to the rear seats, which are slightly less occasional than those of the 911. The huge, tinted and heated, curved rear window, mounted in a thin frame, doubles as a tailgate, a sort of sporting estate car facility. This bodywork shrouds a front-mounted, in-line, four-cylinder engine driving the rear wheels through a transaxle, like the Alfetta and, to avoid the wrath of Lancia Owners' Club members again, the Lancia Aurelia and Flaminia.
Not only does the 924 use parts from mass production saloons, it has commercial vehicle affinities too: the cast-iron, five-bearing engine block is shared with the new Volkswagen LT van (since the 924's introduction, the Audi too has been announced with it too). Its bore and stroke are 86.5 rm. X 84.4 MM., giving a capacity of 1,984 c.c. For its more sophisticated Porsche purpose the block is capped by an aluminium cylinder head, in which is carried a single, belt driven overhead camshaft operating two valves per cylinder. Bosch K-Jetronic fuel injection is fitted. The engine is canted over sharply to the right and has an aluminium sump. This water cooled engine produces a respectable 125 b.h.p. DIN at 5,800 r.p.m just 3 b.h.p. more than the twin-overhead camshaft, carburated 2-litre Alfa Romeo engine, and 121.5 ft. lb. torque at 3,500 r.p.m. 8.5 ft. lb. less than the Alfa.
A single dry-plate clutch is mounted at the engine end of the drive-line. The drive is carried from here to the rear-mounted gearbox through a torque tube, in which the driveshaft is carried in sealed bearings. Only four forward gears, of Audi origin, are carried in the transaxle (automatic transmission is optional) and the ratio of the spiral bevel final drive is 3.44 to 1. The differential does not have a limited slip device. A hefty exhaust system, mounted on the torque tube, adds to the rigid link between engine and transaxle. The torque tube is used to mount the gear linkage, too.
For a 1980s-destined Porsche model, the choice of VW Beetle rear suspension might be thought to be carrying the idea of borrowing mass-production saloon parts a bit too far, though it has to be admitted that it works well in all respects other than ride. Semi-trailing arms are carried by a separate cross-tube in which transverse torsion bars, one per wheel, are mounted. The front suspension is by McPherson struts and wishbones. There are double-acting, telescopic, hydraulic shock-absorbers all round.
For some unfathomable reason, front and rear anti-roll bars are not fitted as standard. To have these pieces of 20 mm. and 18mm. bent wire fitted, as on the test car, costs an extra £80, just one of the essentials listed as "extras" for this £6,986 car. More of that grouse later.
Brakes are not optional, however, though they are borrowed from an Audi saloon, which means the utilisation of discs at the front and drums at the rear, the drums ensuring an efficient and potentially trouble-free handbrake, at the end of the cables operated by a floor-mounted lever on the driver's right-hand side. The test car's brakes were a trifle spongey and over-servoed, though providing good stopping power until this Porsche was punished very hard, when some fade was obvious.
Inside the cockpit the 924 is more reminiscent of a current f.w.d. VW than a Porsche, the most obvious VW-inherited deficiency being not so much the vast acreage of fascia plastic as the inferior positioning of the auxiliary instruments down in the centre console.
No longer does the tachometer gain pride of place in the centre of the deeply-recessed main instruments, all of which have rather nasty, Avenger-type, domed lenses. There is some reflection from these in the screen at night in unlit streets. The VW switchgear is good, the left hand of the positive-action stalks operating flashers and headlamp beam, the right hand the two-speed plus intermittent wipers. Remarkably, the wiper pattern remains continental, like the BMW 2002, so that while the passenger gets clear vision round the screen-pillar area a tall driver has to contend with an unwiped corner area. Auxiliary switches are mounted in the instrument console. The driving position is excellent, except that the fixed, almost vertical steering wheel is set too close to the thighs, particularly when the top part of the slightly oval wheel is wound round on lock. The delightfully stubby gearlever (only the rubbery knob protrude from the gaiter) is ideally placed in the centre console, a wrist-flick from the plastic-padded wheel rim. Sorry, leather rimmed wheel, if you have forked out £40 for such an option.
The front seats are straight from the 911 series and almost beyond reproach, though, just as I do in the 911, I ended up with an ache across the shoulders after a long journey.
Audi-VW pedals allow heel-and-toeing but herein lay a fault on the test-car which almost spelled the end of 924F. The throttle stuck wide open at maximum revs in the 60 m.p.h. second gear at a most inopportune moment just before a 90 degree left-hand bend flanked by rather stout walls. The ignition key took some finding in what was at that stage still a strange car to me, but the situation ended safely. I had to put up with this jamming throttle for the rest of the test, except for a short-lived temporary cure, but learnt to feel the tell-tale click as the throttle pedal jammed, so that I could retrieve it with my toe. The moulded, plastic organ pedal was sliding off the end of the shaft, on which it should have been held by a nylon washer and circlip, of which there was no sign, even beneath the carpet.
Deeply-shaped rear bucket seats are well contrived, with the added advantage of the back rest folding forward to provide a flat boot area. I carried two adults in the back seats (and a dog in and out of the rear shelf) without too much discomfort for any of us. The rear seats are trimmed in pleated vinyl, whereas the front seats have attractive pin-striped cloth centres. Looped carpet, of not particularly good-looking quality, covers the boot/cockpit floor areas. A most sensible, pull-out roller blind is attached to the rear seat backrest to enable boot contents to be hidden. Deep wells beneath flaps in each wheel arch provide more secretive stowage. The boot itself is disappointingly shallow, though wide in area; a full-face crash-helmet can only just be squeezed beneath the roller-blind cover. On the other hand, most 924s are likely to be used two-up for serious journeys, when the rear seat can be folded to afford very adequate suit-case space. That vast, hydraulic strut-supported rear window gives very easy access to the whole area; it needs closing carefully to ensure that each of the two catches, one on each side, is properly located. A lockable glovebox provides additional stowage for valuables; like the boot it has a light which only operates manually when the sidelights are on.
Surprisingly for such a safety-conscious company as Porsche, the very heavy, full-width bonnet hinges at the rear, albeit located at the front by a substantial safety catch as well as the normal catch, which is released from within the cockpit. The underbonnet layout is very professional, very neat, the array of injection equipment and braided fuel lines not too off-putting. Indeed, the distributor and dip-stick offer notably easy access, though the four plugs are more evasive. I wonder why the alternator is fitted in the cramped, hot space ahead of the branched exhaust manifold, tucked away beneath the right-hand side of the engine, necessitating a cooling-air funnel from the front of the car, when there is loads of room on the opposite side of the engine?
Close examination of the 924's smooth flanks, clad in beautiful, glass-smooth metallic green paint on the test car ("metallic" spelling a £230 extra), reveals a finish of superb quality, well up to Porsche standards, though the tatty Porsche transfers were peeling off the sides. Such attention to finish is more than skin deep in the 924's case, for it shares the 911's Porsche Longlife guarantee a one-year unlimited mileage warranty with a six-year guarantee against under-body corrosion, including all load-bearing areas.
To maintain the smooth shape the Hella headlights retract neatly into the nose, operated by a single electric motor with manual emergency winding facility. The headlights give an adequately powerful beam and spread. A minus point is that the headlamps are raised automatically, and unnecessarily, with the sidelamp switch. A plus point is that daylight flashing is by means of auxiliary lamps in the front bumper.
Curiously the engine usually insisted upon starting on three cylinders hot or cold, accompanied by a waddle cods shake upon its extremely flexible mountings. Two other 924s have experience of in Britain shared the same habit. The missing "pot" returned after a second or two and henceforth the engine fired cleanly and pulled strongly even from cold.
I was going to say "ran smoothly", but this the Audi-derived 2-litre "four-pot" does not do. The immediate impression of anybody who either rode in or drove the test car was the general aura of harshness, roughness and noise which pervaded every journey, however short. I seriously wondered whether the Weissach noise, vibration and harshness engineers were consulted when the 924 was evolved. The aforesaid engine was harsh practically all the way through to its 6,500 r.p.m. rev. limit, most unpleasant. Even worse was the road noise, considerable bump, roar and rumble emanating from the 185/70 14 Uniroyal radials on any sort of surface, but especially on deteriorating, rough-cast tarmac. Those Uniroyals are part of the deal when you invest £264 in the optional 6J alloy wheels; standard wear is 5 1/2J steel wheels shod with 165 section tyres. Porsche GB suggested that the smaller tyres would prove less harsh, but seas so fitted they loaned me briefly seemed not a great deal better. It also had exactly the same annoying creak from the nearside door-seal whenever any stresses were put on the body.
Beyond pin-pointing the tyre noise it is difficult to be specific about the origins of harshness and vibration, of which one is permanently aware. I wonder whether the torque she is acting as a conductor to spread the harshness from nose to tail. The benefits of low wind noise from the sleek shape are lost amidst the road and engine noise. Other noises included a rumble from what I fear may have been a suspect bearing in the transaxle and a more alarming rumble which made a sudden appearance every time the car was thrust hard into a left-hand corner. We pin-pointed this to the exhaust manifold banging against the offside chassis rail, and mere thus able to help Porsche GB with advice, for they had been unable to trace a similar problem on another journalist's long-term test 924. Part of the cause seemed to be excessively flexible engine mountings: it was possible to waggle the engine and transmission unit around vigorously by hand, either by grasping the cam cover or shaking the exhaust pipe. And all the mountings were in place and unbroken.
On a more pleasant note, Porsche have achieved highly creditable performance levels in relation to power output against weight. Their claimed 0 -60 m.p.h. in 9.9 sec. from this 125 b.h.p. 21 1/4 cwt. car is easily beaten and the 125 m.p.h. maximum is a very genuine figure. At the same time the 924 feels terribly overgeared in the intermediate ratios, as these approximate speeds in the lower three ratios reflect: 36 m.p.h; 61 m.p.h., 97 m.p.h. Such high intermediate gears give deceptive, but very unexciting performance if one is to remain relatively legal. On the one hand the engine needs to rev. to give of its best, on the other, if taken into its happiest rev. band it represents a quick may to lose one's licence. The combination of such high intermediates and modest torque is just not right. What this car needs is a five-speed gearbox with sensibly spaced ratios, using top as an overdrive in conjunction with a lower final drive ratio. And why not five-speed gearbox in a £7,000 car, indeed? That having been said, Porsche should be complimented on the pleasantness of the positive, short-shift gearchange, splendid for a long-travel, rearwards linkage, though the lack of a fifth gear must have reduced the difficulties involved. Clutch action is pleasant and light.
This "small" Porsche is not a small car by any means in sports car terms, being 13 ft. 8.5 in long and 5 ft. 5.2 in. wide. But it shrinks into a very easily placed car on the road, largely because of excellent all-round visibility. The nose does drop away, but not so dramatically that you wonder where on earth it is, like in a Maserati Bora or something of that ilk. Its steering is modestly weighted for parking, while its tight steering lock struck me as one of the 924s better features.
Moving into the realms of handling, the 924 begins to show its true ancestry at last. The each and pinion steering is light and precise, exhibiting that traditional Porsche "jiggling" which is at first a little exasperating, but at last so communicative, passing its own code to the skilful driver. On the road it proved essentially a neutral car, on the circuit it had a tendency towards too much understeer to be fun, though with the right amount for safety, too slow on most of our adhesive Hertfordshire circuit corners to enable it to be thrown out of this attitude. Repeating the comparison I mentioned in the Fiat X1/9 test last month, Andy Dawson's time round that circuit in the 924 was 1 min. 24.3 sec. against 1 min. 25.1 sec. for a TR7 and 1 min. 26 sec. for the X 1/9. On the other hand, on the twistier, smoother surfaces of our Surrey test track it was easy to take the car to the limit, with a result that was not entirely satisfying: roll oversteer took over quite abruptly, and though each time this happened control was kept without hanging too far sideways, the impression was a nervous, knife-edge one. To lift off in the middle of such a procedure is to invite disaster, for the nose comes in quickly, leaving the tail wondering what to do. Under most circumstances on the road, however, most drivers will find the roadholding and handling exemplary, while stability under braking is helped by the front suspension's negative roll radius.
One thing I had almost forgotten which makes the 924 most un-Porsche-like is an effective, uncomplicated, consistent, heating and ventilation system, a benefit of a water-cooled engine.
One of the claims made by Porsche for the 924 is exceptionally good fuel consumption. This may be so on constant speed motorway work, in which conditions our test car averaged 27-28 m.p.g. -still unexceptional. However, general motoring, including a bit of every sort of condition, including London commuting, showed an average of 23 to 23.5 m.p.g. In the same conditions, the last 2.7-litre 911 I had on test averaged almost 22 m.p.g. on 2-star fuel, whereas the 924 insists upon 4-star. Its fuel tank holds 13.6 gallons. By current standards oil consumption was high, at 2 pints in 1,000 miles. Interestingly, my figures for the Motor Sport test car were very similar to those of another 924 tested by our sister journal Motoring News, which suggests that they are representative.
Towards the end of the test I was mellowing to this baby Porsche as a means of transport, but on the whole I can only reflect upon it as blandly unexciting, characterless, without much charm. Its biggest problem is that of noise, vibration and harshness, which may well have been worse in this test car (though we can only judge by whatever car the manufacturer or his agent considers it is right to proffer), but was by no means lacking in other examples we have experience of. The gearbox is out of character too. There is a rumour that Porsche will eventually fit an engine of their own design, presumably fitted to their own gearbox and perhaps has the price might be justified. After all, the test car, complete with stabiliser bars, metallic paint and alloy wheels, but not including its Blaupunkt radio, cost £7,573, a lot of money for a car which does not feel fully developed. My own £7,573 would go on a second-hand 911, or I would save £2,500 by buying an Alfetta GTV 2000. - C.R.