Road Test -- Porsche 944 Turbo Cabriolet

Fresh air turbo

Porsche Cars Great Britain Ltd Managing Director Peter Bulbeck and his slightly reduced team of Reading, Berkshire, employees are in no mood to take more hostile press comment over UK sales, particularly those of the 944, which ceased production at Audi of Neckarsulm recently. The resurrection at Zuffenhausen is not scheduled until "early 1992". The Reading Porsche ("Remember. . . . Porsche is a two syllable word", nags their press briefing) contention on 944 sales is, "we had to provide sufficient production to tide ourselves and our dealers through a very long production pause. From current information, with 944 sales so far this year at 450 units we have probably got this about right, or too few if Mr Lamont is right and the third quarter sees an upturn", says Mr Bulbeck wryly. "In yearly terms the total sale of Porsches to Britain this year is likely to be 2271, rather above our target of 2000 units for 1991", continues the British Porsche director.

A look at the SMM&T statistics records that 2801 Porsche sales were achieved in 1990 Britain, some 20 per cent up on the forecast for 1991. That does contrast with "Porsche sales are over 50 per cent down" gleefully reported in a May edition of the Daily Mail, and a source of considerable dissatisfaction, chez Porsche GB.

Over 860 miles in a frequently sunny May week with the limited edition (100 are in Britain) 944 Turbo Cabriolet, we uncovered a 944 that may well set the customers queuing once more. True, Britain is gripped by one of the worst recessions the post-war generation has seen (Porsche ownership ages average 39), so none but the dreamers would expect anything other than an overall sales loss, especially as when Porsche used to sell over 3000 cars a year in our country "over 2000 of them were £20,000" in Peter Bulbeck's words.

That the popular press crows about Porsche distress is also unsurprising, given the Yuppie era, which tainted Porsche, BMW and Volkswagen (for Golf GTI) pretty evenly, thus arousing much jealousy amongst those who miss no opportunity to denigrate exceptionally enjoyable and effective cars for social rather than rational reasons.

Peter Bulbeck's explanation of stock levels was timely, but we are not totally convinced. We took the car back to Reading and were surrounded by what seemed to be the other 99 turbocharged Cabriolets and plenty of general stock (including more 911s than I have seen since on a factory visit). I was ready to ask how long it would be before the discount Porsche became a public reality rather than a back door deal. In fact our test car cost increased by virtually £1000 after the VAT increase to 17.5 per cent, bringing the price of 250 horsepower fresh air motoring to £46,994. For that considerable sum (though compare it to a Jaguar V12 convertible, now priced at £50,600, and the 911 cabriolet from £54,268) the inline four-cylinder Porsche provides deep driver satisfaction.

Statistically the sub-6-second 0-60 mph abilities were accompanied by 148.5 mph with the hood up around Millbrook bowl, a maximum so far short of the 162 mph factory claim as to worry us severely, for Porsche is always scrupulously honest in its performance claims. Then we noted that other independently timed 944 Coupé turbos of 250 horsepower specification have recorded maximums in the 152 mph area, and another monthly magazine realised 151.3 mph from "our" demonstrator.

Just how much the car was enjoyed at exhilarating speeds with the hood down can be surmised from an overall 17. 7 mpg of cheaper unleaded; the test week featured three circuit visits (only one for formal testing) so that only once did we approach the official Urban return of 21.2 mpg.

The UK Range

There are now three primary 944 models on offer in Britain. They begin with the normally aspirated 3-litre S2 coupé of 211 bhp. Much underrated, this 146 mph 2+2 has fine handling using many features of the 250 bhp 944 Turbo, but the S2 costs from £36,458 rather than £43,648. At £41,794 there is an S2 Cabriolet which shares many of the features mentioned here, bar the turbo-charged powerplant and a consequent 39 bhp.

Unless we have a 911 turbo cabriolet listed in Britain once more, the turbocharged 944 is one of the quickest sources of open-air motoring available in the UK. It is also comparatively rare at the 100-off limited edition figure and is also well equipped for our market.

Standard 944 Turbo Cabriolet features include anti-theft alarm (prickly enough to be activated by practice-day circuit traffic at Castle Combe), Blaupunkt Symphony stereo radio and cassette player, and air conditioning. Cooled air is far from a nonsense when the hood is raised. There is also electrical operation for the majority of the extended hood opening and closing routine.

Technical Analysis

Dimensionally and technically the 944 remains based upon the front engine, rear transaxle layout that emerged from the 924 base a decade ago. This has been progressively developed to accompany the constant escalations in power that the turbo era wrought. A 944T has 87 bhp more than the original 163 bhp.

So far as the body is concerned, the presence of the hood is accompanied by a 60mm/2.36 inch decrease in windscreen height. It also features rear seats that fold forward to allow access to the boot for objects such as ski storage. Complete with all the electrical motors for the hood and the standard equipment listed, weight has increased marginally to 1400 kg, 10 kg more than the normally aspirated 944 Cabriolet but it is rated the same kerb weight as a 944 Turbo Coupé. Although the double skinned hood saves lbs over sheet steel and glass, the Cabriolet model is extensively stiffened so that "effectively two floorpans are welded together", says Porsche publicity. All recent 944s were built of galvanised steels and warranted for 10 years, and the Turbo Cabriolet also carries warranties against mechanical failures over two years, plus three years protection for the 4-layer paint application.

Mechanically Porsche stress the link back to the Turbo Cup contenders as providing the unchanged 250 bhp engine specification and the strengthened 5-speed transaxle with external oil cooler, plus a standard limited slip differential with a discernibly sporting setting. The spring rates (torsion bar rear) are actually not quite so severe as in the days of the original 250 bhp 944 SE turbo, but the independent system by ubiquitous MacPherson struts and trailing arms is firmly restrained by fore and aft roll bars and accurately located by muscular aluminium arms. Aluminium, albeit specifically cast aluminium, is also utilised to create the 7.5 inch breadth front wheels and 9 inch rears that supported Pirelli P700Z covers on the test car.

The braking system is very special in action, but routine to Porsche. They describe it simply as "the 928 series 4 ABS braking system with its larger, four piston, fixed caliper disc brakes. More than 11 inches in diameter, front and rear units are vented and are said to be capable of returning the Turbo Cabriolet from 62.5 mph to rest in three seconds. That is about half the time that the large turbocharger version of the single camshaft 2.5-litre (two valve per cylinder, rather than the DOHC quad valves of the 3.0 S2) takes to accelerate to said 62.5 mph/100 km/h barrier.

Maximum torque amounts to nearly 260 lb ft, but the K-26 turbocharger makes you wait until 4000 rpm for the peak; harder drivers will want 4000 to 4500 rpm indicated before the responses are those expected of 250 bhp.

Cabin

The 944 cockpit has progressed dramatically over its 924 origins and now features clear red, white and black instrumentation in four primary dials, plus a 4-spoke, leather rim, steering wheel that no longer seeks to loll on your thighs, but still lacks an adjuster. The controls are more scattered than one would attribute to Teutonic minds, leaving the hazard warning flashers over toward the glove box. I misunderstood the electrical mirror adjustment symbol long enough to cause annoyance.

In fact the Cabriolet 944 is one of those cars where even the experienced driver has to resort frequently to the handbook for guidance. Initially I had the advantage of Claire Knee, Press and PR Assistant, showing me where the hood unlocking keys were (gear lever console box) and the necessity of pulling the hood back into contact for the final few millimetres prior to relocking the top in the up position.

Subsequently there were no problems in swiftly deploying the hood, so long as one remembered that the engine had to be off, the ignition key turned one click and the gear lever in neutral, but other niggles nagged at our attention to the point where we wondered whether living with the car might actually be worse than simply borrowing it for a favourable week. To release the boot, for example, you stoop into a footwell, press a button which electrically releases the lid. . . That is, so long as you have switched the ignition on. Why use the internal release all the time? Because, if you fiddle with the boot without having primed the ignition, you set the UK standard burglar alarm off.

The doors never shut at the first attempt, and the driver's door locking catch was abnormally stiff to release. Other minor gripes were the door jamb location of the handbrake and the electrical operation of seat squab, front and rear, minus the most important horizontal plane. Why not dispense with the minor electrical goodies in a small convertible anyway? Or build a "power-everything", Mercedes 500SL style, in the first place? Fit and finish of the Porsche hood was outstanding and, if I have driven a quieter hood-up four-cylinder convertible, the Porsche has eclipsed its memory by its composure at an indicated 80 mph. The low lines of past Speedsters is hinted at in the low roofline and this extended wheelarch 2+2 gnome seater is the most rakish of roadsters in red. Also of exemplary quality were the leather-trimmed seats, and the seating performed its role through easy access and reassuring location in a manner that deserves blatant copying for the benefit of a wider populace.

At the Wheel

Look at those flexibility figures and see just how fast a turbocharged four responds to a demand for everyday speed, if the driver is alert. In third gear the 944 Turbo Cabriolet demands just over 3.5 seconds to zip from 50-70 mph. Be lazy, and it will take almost three times as long in fifth for the same increment.

So long as you are prepared to be involved with the eerie smoothness of this large unit at higher rpm, it is the finest turbocharger installation we have ever experienced. A Porsche purist with a priority for effortless road response might argue that the old 225 bhp Turbo was a more friendly beast. Yet the sheer energy available on demand in the more powerful, and more recent, variant is addictive.

The motor has a magnificent note beyond 5000 rpm, spinning merrily beyond 6000 rpm with heartening vigour that contains not a trace of traditional four-cylinder roughness. The half-litre larger normally-aspirated S2 power unit also denies its large cylinder bores, but for this writer the counterbalanced 2.5-litre is better still. We can understand Porsche employee annoyance with those who turn their noses up at the model on the basis, "oh it's only got a four-cylinder engine". The fact is that a Porsche counterbalanced four is a lot smoother than many mass production sixes, without the obvious weight penalties. Acceleration figures would not normally preoccupy our testers, but those of the 944tc do bear longer study. The leap to 30 mph is accomplished in 2.2 seconds, a fine traction achievement by Porsche for a powerful front-engine, rear-drive, turbo car, only equalled by the Ford 4x4 RS Cosworth in recent months at Millbrook track. By 60 mph the Porsche would be ahead of the 220 horsepower Ford (5.9 seconds versus 6.5), but the pair are back on parity by 100 mph and less than 17 seconds have elapsed (a tenth between them in our comparative experience). We did not record even fractional differences between their 0-120 mph abilities, 26.8 seconds apiece.

Naturally, the Porsche was more difficult to "launch" than the 4x4 Ford, demanding a 4500 to 5000 rpm clutch engagement. Thus abused, its excellent elapsed times were sometimes accompanied by the kind of axle hop that we had hoped was laid to rest with the Marina and Hunter saloons of the Seventies.

The maximum speed runs were achieved without fuss, or the roof showing any inclination to depart at nearly 150 sustained mph. Stability was excellent; note that this is one of the few sporting cars on the road today without an obvious tail spoiler.

Porsche preferred to manage the air underneath the body on this model, providing front-end ducting to assist braking whilst the rear features a small under-bumper "blade" that appears to do some good. (TWR tried an under-bumper spoiler on their European racing XJ-S V12s of 1984; contemporary team personnel felt it was "purely to upset the opposition, it does no discernible good at all".)

The Turbo Cabriolet chassis is almost old-fashioned in its hard low-speed ride and the steering will certainly tell you how 225 low profile tyres squirm away from adverse cambers, or the crown of a minor road. Yet there was not a solitary rattle exhibited by the red roadster, even when regularly pressed into 20-30 mph coverage of a by-road that was tarmac before South Oxfordshire District Council discovered that neglect is the cheapest short-term maintenance option.

The steering is not as sharp as you might expect in a stiffly sprung chassis, but there is plenty of variable power assistance feedback and the levels of grip now routinely obtained are truly admirable. In track use a 944 turbo can be understeered into a third or fourth gear corner with a modest amount of optimism and excess velocity. By the time you are really beginning to worry if you will ever get the nose to point at an apex, the turbo boost and power band are fully engaged. The result is a long spell of neutrality, when the 944 can be balanced with a confidence that is rare in conventional cars.

At very slow speeds and high boost engine speeds you may edge the rear tyres out of line, but generally you are unlikely to get the 944tc to the point where a spin will set in. We have not encountered any such sliding tendencies in hard road use. As intimated earlier, the brakes are outstanding; further comment from us would be patronising, for we cannot think of a public road use improvement we would make.

Verdict

The 944 Turbo Cabriolet offers a rapid and honest sports car, but one without the traditional drawbacks. The ride is firm without inflicting jarring shocks on the occupants, but the harder you drive, the more sense it makes.

Its closest competitor is the turbocharged Elan SE. At half the money requested for a Porsche 944tc the £22,490 new Elan is tempting, but Porsche customers will probably pay the extra to avoid front-drive and gain on quality. The Elan is a convincing ensemble, but performance is less than that of the German soft top: our figures show the Lotus recording 134.5 mph, 0-60 mph in 6.5 sec and 0-100 mph in 19 seconds.

Over £50,000 is required for more sheer straight-line soft-top speed than the 944tc musters, only the bigger 500SL Mercedes stretching into the 155 mph bracket. And the V8 Mercedes would still lag in acceleration to the despised four cylinders. Neither can Stuttgart supply the immense driving pleasure that Porsche provides, all backed up with evidence of conscientious durability development and some handling lessons learned in motor sports.

The 944 Turbo Cabriolet is a limited edition that may well be worth collecting. It was certainly one of our better motoring experiences of 1991. -- JW

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MOTOR SPORT TEST RESULTS -- PORSCHE 944 TURBO CABRIOLET

SPECIFICATION

ENGINE: Engine water-cooled, light alloy construction, inline four cylinders; twin contra-rotating balance shafts; SOHC, 2 valves per cyl. Capacity: 2479cc (100 x 78.9mm). KKK K26 turbocharger and inter-cooling; max boost 0.75 bar/10.7 psi. Bosch Digital Motor electronic ignition and fuel management with over-run fuel cut-off. 8:1 cr, 3-way catalytic converter. Max power: 250 bhp @ 6000 rpm. Peak torque: 258.5 lb.ft @ 4000 rpm.

TRANSMISSION: Front engine, rear drive via 5-speed manual transaxle (rear-mounted gearbox); limited slip differential with 40 per cent preload.

GEAR RATIOS First: 3.50; Second: 2.06; Third: 1.40; Fourth: 1.03; Fifth 0.829..... 25.46 mph per 1000 rpm; Final drive: 3.375.

BODY: Galvanised steel 2-door 2+2 convertible. Nose in polyurethane; fabric hood with 95 per cent electrical operation and manual locking/unlocking. Petrol tank of 80 litres/17.6 gallons

DIMENSIONS: Wheelbase 94.5 in/2400mm; front track 57.95 in/1472mm; rear track 57.13 in/1451mm; width 68.3 in/1735mm; length 166.4 in/4230mm; height 50.2 in/1275mm. Kerb weight: 2948lb/1340kg.

FRONT SUSPENSION: MacPherson struts, double-acting hydraulic damping, coaxial coil springs, aluminium lower arms, 26.8mm anti-roll bar. Steering, rack and pinion, 3.24 lock-to-lock on an 18.85:1 ratio; hydraulically power-assisted; 10.75 metres turning circle.

REAR SUSPENSION: Independent, semi trailing arms, torsion bar spring per wheel; telescopic hydraulic dampers and 16mm anti-roll-bar

BRAKES, WHEELS, TYRES: Brakes: Power-assisted, vented front and rear with four-piston calipers; 11.1 in/282mm diameter front discs; rears 11.38 in/289mm diameter. Bosch ABS electronic antilock braking. Light alloy 7.5J x 16 in front wheels; 9J rears. Pirelli P700Z of 225/50 ZR 16 front and 245/45 ZR 16 rear

PRICE: £46,993.54, UK taxes paid.

MANUFACTURER / IMPORTER: Porsche Cars Great Britain Ltd. Bath Road, Calcot, Reading, Berks RG3 7SE.

CLAIMED PERFORMANCE: Max speed 162 mph; 0-62 mph 5.9s

TEST RESULTS

Conducted at Millbrook Proving ground using 1991 Correvit electronic measuring gear. Weather conditions: Overcast, dry tarmac

ACCELERATION: 0-30 mph 2.22 seconds; 0-40 mph 3.40 seconds; 0-50 mph 4.54 mph; 0-60 mph 5.91 (5.86) seconds; 0-70 mph 7.98 seconds; 0-80 mph 10.41 seconds; 0-90 mph 13.10 seconds; 0-100 mph 16.80 seconds; 0-110 mph 21.12 seconds; 0-120 mph 26.85 seconds (minus air conditioning)

FLEXIBILITY: Third gear 50-70 mph 3.68 seconds; Fourth gear 50-70 mph 5.30 seconds; Fifth gear 50-70 mph 9.30 seconds

Standing 0.25 mile/400 metres: 14.98 seconds @ 93.8 mph

Maximum speed: Millbrook 2.029 mile bowl, lap speed, 148.52 mph

Maximum gear speed @ 6400 rpm: First 37.4 mph; Second 63.2 mph; Third 91.2 mph; Fourth 120 mph

Overall fuel consumption: Test Average 17.7 mpg; Best 20.72 mpg; Worst 13.62 mpg

Government mpg figures: Urban 21.2 mpg; 75 mph 30.4 mpg; 56 mph 39.8 mpg