Porsche 911 turbo at 50: icons of the air-cooled era

By Ben Barry

| 8 May 2024

Classic & Sports Car – Porsche 911 turbo at 50: icons of the air-cooled era

Swollen hips covering fat, low-profile tyres, ‘whale-tail’ spoiler, italicised script on the engine cover…

Nothing figuratively or literally says you’re packing boost quite like the rear end of a Porsche 911 turbo.

This year the landmark model celebrates 50 years since its debut at the 1974 Paris Salon, so to celebrate we have assembled the air-cooled bloodline that tells the first half of that story.

Two 930-generation Porsche 911 turbos (closest) meet their air-cooled siblings

The Stuttgart marque was always going to adopt turbocharging sooner or later – after all, the technology is near universal these days to cut emissions and save fuel.

But when Porsche first used exhaust gases to spin up a turbine and force air back into the engine, it was all about performance and motorsport.

When new rules outlawed Porsche’s 917 for 1972, following back-to-back Le Mans wins, it turbocharged the flat-12 prototype and ran rings around the opposition in the North American Can-Am series.

Then, when the oil crisis rained on that parade, Porsche turbocharged its existing 911 racing steed.

The 2.1-litre Carrera RSR turbo was initially campaigned as a prototype because Porsche sold no comparable production car, but the more showroom-relevant Group 4 and Group 5 competition required at least 400 road cars to be produced.

Italicised ‘turbo’ script below the Porsche’s immense ‘whale-tail’ spoiler

The Porsche 911 turbo shown at Paris in 1974 (internally codenamed and known widely as the 930) was the start of all that, with a 3-litre engine that shared its bore and stroke with the RSR race car, but added a single KKK turbocharger.

Together with a lower (6.5:1) compression ratio, Bosch K-Jetronic fuel injection and just 0.8 bar of boost, it made 260bhp at 5500rpm with 253lb ft of torque at 4000rpm.

Drivers of the standard 2.7-litre 911 had to work their cars a lot harder for less performance – 210bhp at 6300rpm and 188lb ft at 5100rpm – but, then again, the turbo was almost twice the price, at DM67,850.

The 930 was an aggressive revamp of the 911, but the 3.0 (closest) has aged gracefully

The rest of the 911 was also upgraded to make the most of the extra power flowing to its back wheels – hence rear wheelarches flared to accommodate 15in alloys that were 8in wide at the rear (7in at the front) in road trim, along with beefed-up semi-trailing arms in cast aluminium rather than pressed steel, uprated wheel bearings and the signature spoiler to squash it all into the ground at speed.

John Brewer’s beautiful Guards Red right-hand-drive 930 is quite literally a homologation car, being chassis number 80 of that initial run of 400, and was first delivered to Australia.

Climb aboard and you sit low in sports seats, their tartan centres squishing beautifully under your weight to form themselves around you.

The Porsche 911 (930) turbo 3.0 tends to understeer when pushed

Porsche iconography and idiosyncrasies are all around: the signature five dials that fan out across the instrument cluster, the view over that plunging bonnet between raised wing peaks, and floor-hinged pedals heavily skewed inboard.

This car’s optional extended steering column makes the chunky, three-spoke wheel an easier reach if you’re 6ft-plus.

The 911 turbo is no pseudo-racer.

Then, as today, the model offers performance with luxury, where the naturally aspirated RS models were and remain a much more raw experience.

Tartan seats for the 930-generation Porsche 911 turbo 3.0

Convenience features even on this early car include air-con, electric windows, and part- or full-leather upholstery, and many of these luxuries were carried over to the Group 4 934 racer, simply because minimum weight limits were high so there was little need to bin them – the upshot being that the racer was only 100kg or so lighter than the 1195kg road car.

For a turbocharged engine, the 3-litre feels surprisingly responsive to a breath of throttle, its revs flicking up eagerly, though you notice its muted refinement, with the usual tingly rasp of the flat-six dulled by a fuzzier turbo timbre.

Accelerate in a straight line and the generous capacity makes the 930 tractable in a way that laggy contemporaries such as the BMW 2002 turbo aren’t, but you still need 4000rpm or so to get the full-boost adrenalin rush, at which point the car squats on its haunches and pings off down the road until the needle swings around to that slightly lower 6400rpm redline, ready for another cog.

‘Drivers of the standard Porsche 911 had to work their cars far harder for less performance – but a turbo was almost twice the price’

Not that you will be shifting gears too often.

The gearlever is long, pretty laissez-faire to slot home and comes attached to a then-new four-speed Type 930 gearbox – the turbo Carrera’s Type 915 transmission had proved troublesome at Le Mans in 1974 – with galactic gear ratios.

This all has a profound impact on the way the 930 handles compared with other ‘impact-bumper’ Porsche 911 models of the era, even if the underlying balance and feel remain familiar.

The steering bubbles with road-surface nuance, but has usefully more heft than the floaty feel of the Carrera RS 2.7 (at 120kg heavier than a 2.7 RS Touring, the turbo feels generally more substantial).

The Porsche 911 turbo 3.0 offers best access to that rear-mounted flat-six

The feathery front end is both keen to turn in and limits how much speed you can carry before the dreaded understeer takes hold; and that heavy rear end allows you to dig into the traction early.

Turbo lag, however, makes it hard to exploit this balance on the throttle alone, almost like a music video with the vocals out of sync – there’s such a delay as the boost brews that it has little bearing on adjusting the car’s trajectory.

Legend might bill the 930 as a widowmaker, then, but the chances of kicking the tail out under power feel pretty remote.

The Porsche 911 turbo 3.3 (closest) introduced a 300cc capacity increase and a higher compression ratio

It’s more likely you would need to pitch this car into a corner aggressively, off-throttle, to get it out of shape – and, given that the brakes are pretty marginal and the boost kicks hard, there’s a good chance of arriving at the apex a bit too hot.

Think more spirited road trip than race track, and this early turbo is in its element.

If the 930 turbo was a developmental leap, the Porsche 911 generally languished over the following decade, with boss Ernst Fuhrmann switching the company’s attention to the new front-engined era, kick-started by the 924 and 928.

The Porsche 911 turbo 3.3 arrived in 1978, boasting 296bhp

Not that the turbo was entirely neglected – in its first few years on sale, Porsche engineers added a bypass valve, increased boost pressure and upped the wheel diameter to 16 inches.

The big step came in 1977 for the 1978 model year, however, and would set the template for the 930 right through to the end of its (extremely long) life in 1989.

Rory Jack’s turbo is an end-of-the-line 1989 car.

Like all 1978-on models, it features the revised ‘tea-tray’ rear spoiler, which replaced the elegant flick of the early car with a larger wing that was necessary to cover a new air-to-air intercooler added to chill the intake charge.

Later Porsche 911 (930) turbos look more muscular

Complete with a 300cc capacity increase and compression ratio hiked to 7:1, output was boosted to 296bhp and 304lb ft of torque.

Other upgrades for this very late car include a new G50 five-speed ’box, cross-drilled brake discs (albeit not the 917-derived rotors of the early 3.3s) and a clutch-disc hub that helped to eliminate the gear chatter of early cars.

This also affected the chassis, however, because it moved the rear-mounted engine back by 30mm, while rear tyre pressures shot up from 34 to 43psi, in part to manage a kerbweight 105kg heftier than the first 930s.

Inside the Porsche 911 turbo 3.3’s 1980s cocoon

Overall, though, the 3.3 is a more positive-feeling drive.

The steering trades the delicacy of the early car for a more substantial feel – no surprise, given the larger wheels and tyres.

The five-speed G50 ’box (added for the final year of 930 production) slots in with more precision and – most important to confidence – the brake pedal offers both superior bite and stopping power.

The performance also has more kick, thanks to a combination of the extra factory boost, this tweaked car’s additional 20bhp or so on top, and the five-speed transmission offering closer spacing between ratios – the latter possibly a more pertinent factor, given these later cars’ additional weight.

The Porsche 911 turbo 3.3 feels a touch edgier than its 260bhp predecessor

In the low- to mid-speed flicks of the Bicester Heritage track, it’s hard to detect a more pendulous effect from the engine being pushed back that bit further, but you do now have the power to work the Porsche 911’s balance on the throttle.

It’s more responsive and involving, though it is easy to imagine the boost kicking in strongly mid-corner, causing an owner to quickly shut the throttle and exit stage left, right or wherever the catastrophic weight transfer took them.

While the 930 turbo soldiered on through the ’80s, Porsche released the revolutionary 959 in 1986 (see below), and intended to use this Group B homologation special’s bones as the basis for a new model to replace the turbo.

That car went under the internal codename 965.

The last 964-generation Porsche 911 turbos got a 3600cc flat-six

Best laid plans and all that…

By the time 930 turbo production ended in 1989, Stuttgart was at a critical juncture, with the recession biting hard and sales slipping from the normal 40,000 or so a year to just 15,000 globally.

Porsche needed a parts-bin special, not a technological tour de force, so it decided to apply the familiar 930 turbo recipe to its new 964-generation 911 – at that point the most significant update in the enduring model’s 26-year lifespan.

Across the 911 line-up, the basic bodyshell was fundamentally carried over, but the new, integrated bumpers made a visual break with the past, while under the skin there was coil-springing all round, plus – depending on the variant – power steering, a Tiptronic automatic transmission, ABS and all-wheel drive.

The Porsche 911 (964) turbo 3.6 is the most exciting car in this group

The 964 turbo arrived in 1991, still with rear-wheel drive, a manual gearbox and a 3.3-litre single-turbo engine, but for 1993 (the final year of production) capacity grew to 3.6 litres.

At a stroke, power was boosted from 316bhp – underwhelming given that weight increased by 170kg over the late 930 – to 355bhp.

That’s the model we have with us today, accomplished racer Ambrogio Perfetti’s beautiful right-hand-drive Aussie import, identifiable as a 3.6 by its blood-red brake calipers and 18in Speedline split-rim alloys.

Porsche 911 turbos gained an airbag-equipped steering wheel from 1991

Weight may have gone up substantially, but first impressions suggest this is the lighter car.

No doubt that’s the power-assisted steering, giving the driver much more confidence to grab the 964 by the scruff of the neck.

The new suspension set-up also feels more competent, with more immediate responses and better control, whether you are braking hard for a corner or tossing it at the apex.

Part of that proficiency is down to this car’s fresh Michelin Cup 2 rubber, with grip far beyond what the original tyres would have offered, but the 964 is still the most dynamically lively of the four Porsches here – and the only one to slide just a fraction as the boost kicks in through a third-gear kink at Bicester.

The Porsche 911 (964) turbo 3.6’s potent 355bhp flat-six and rear-drive make it entertaining on track

But offered the choice of just one of the rear-wheel-drive turbos to drive down a twisty B-road as fast as I could, this would be the pick.

Given that the 964 was the last rear-drive turbo, it’s tempting to draw parallels to the GT2 models that made this formula their own just a few years later, but the truth is that GT2s have a much more raw, feelsome character where the 964 is still very much a turbo – punchy in a straight line, entertaining through the bends, but with a level of isolation, refinement and usability lacking in those later, hardcore models.

It’s why Ambrogio uses this example for road trips, including driving it to Le Mans.

The four-wheel-drive Porsche 911 (993) turbo has sensational pace

For all the 993’s undoubtedly big steps forward, and its more mature, more luxurious interior, the final air-cooled turbo still feels very much a logical progression from the 964 – even if, this time, Porsche did manage to transfer learnings from the 959 hypercar.

The new, restyled and more aerodynamic front end suggested as much, plus under the skin there was a 20% stiffer bodyshell some 50mm wider at the hips, together with all-wheel drive and twin turbocharging.

Even basic 993 Carreras made more power than a 930 turbo, but the new 993 flagship stepped up to 402bhp – rising to 444bhp in the turbo S, a dead heat with the 959 in a package that shed 30kg versus the stock version.

The 993-generation Porsche 911 turbo benefits from a more mature cabin

Neil Clifford’s gorgeous example splits the difference between the two, being optioned both with S-spec air inlets ahead of the rear wheels and the factory X50 engine upgrade to 424bhp.

Peak power and torque were pushed up the powerband a little versus the 964, but the 993 is the more flexible unit by a margin.

Where the others wait and build, the 993 is quick from the off and then, when everything ignites, hits the fast-forward button.

Two decades on, it remains an intense experience.

Twin intercoolers on the Porsche 911 (993) turbo

The power-assisted steering is as dextrous as the 964’s, the gearchange and clutch the sweetest of the four, and even on base Carrera models the new ‘Light, Stable, Agile’ rear axle transforms the 911’s handling, giving far more control and more options when you near the rear-engined icon’s limits.

All-wheel drive builds on these foundations to brilliantly soak up the engine’s huge slug of performance, though that’s not to say you can’t use the power to manipulate the 993’s handling.

Fundamentally, the age-old Porsche 911 physics remain intact, it’s just that four-wheel drive changes the way you experience them.

From first to last: these air-cooled Porsche 911 turbos offer performance and luxury

Go a little early on the throttle with some steering lock applied and the power diverts forwards, and you feel the secure, slightly dead-feeling push of understeer, but back off the throttle, sweep that light nose at a fast apex and the 993 swings into oversteer, and lets you steer it on the throttle more readily than the purely rear-driven early cars.

The 993 is the bridge between the Porsche 911 turbo eras: a luxurious, twin-turbo, all-wheel-drive model that left its predecessor’s motorsport link at the kerb, but that air-cooled flat-six provides a common thread to the original, conceived for competition two decades before.

Images: Max Edleston

Thanks to: Sports Purpose; Bicester Heritage

Porsche 959: the 911 unleashed

The Porsche 959 was the marque’s first hypercar, and its technology trickled down to the 911 turbo

The 959 is the missing production-car link in this story, because, while it isn’t actually a 911 turbo, the innovations it pioneered soon improved the breed.

Its genesis goes back to new boss Peter Schutz joining Porsche in 1981 and reversing predecessor Ernst Fuhrmann’s plan to eventually phase out the 911.

Given that the model had been largely neglected since the mid-1970s, Schutz asked chief engineer Helmuth Bott to inject new ideas and new technology.

The Porsche 959 was built to Group B regulations

The result was the Gruppe B concept, which evolved into the production 959, Porsche’s first hypercar.

Taking the 911’s steel monocoque and an air-cooled flat-six as its base, the 959 added aluminium, polyurethane, Kevlar and carbonfibre panels to a longer, more aerodynamic body, while the adaptive suspension, all-wheel drive, sequential turbochargers and water-cooled heads worked witchcraft under the skin.

Making 444bhp and capable of 197mph, the £150,000 959 was three times costlier than a 911 turbo – and still lost money.

Factfiles

Porsche 911 (930) turbo 3.0

Sold/number built 1974-’77/3227
Construction steel monocoque
Engine all-alloy, sohc-per-bank 2994cc flat-six, turbocharger and Bosch K-Jetronic fuel injection
Max power 260bhp @ 5500rpm
Max torque 253lb ft @ 4000rpm
Transmission four-speed manual, RWD
Suspension independent, at front by struts, longitudinal torsion bars rear semi-trailing arms, transverse torsion bars; telescopic dampers f/r
Steering rack and pinion
Brakes discs, with servo
Length 14ft 1in (4290mm)
Width 5ft 10in (1775mm)
Height 4ft 3in (1320mm)
Wheelbase 7ft 5in (2268mm)
Weight 2635lb (1195kg)
Mpg 22
0-60mph 6.1 secs
Top speed 153mph
Price new £14,749 (1975)
Price now £80-375,000*

Porsche 911 (930) turbo 3.3

Sold/number built 1978-’89/17,425
Construction steel monocoque
Engine all-alloy, sohc-per-bank 3299cc flat-six, turbocharger, intercooler and Bosch K-Jetronic fuel injection
Max power 296bhp @ 5500rpm
Max torque 304lb ft @ 4000rpm
Transmission four/five-speed manual, RWD
Suspension independent, at front by struts, longitudinal torsion bars rear semi-trailing arms, transverse torsion bars; telescopic dampers f/r
Steering rack and pinion
Brakes discs, with servo
Length 14ft 1in (4291mm)
Width 5ft 10in (1775mm)
Height 4ft 3in (1310mm)
Wheelbase 7ft 5in (2272mm)
Weight 2866lb (1300kg)
Mpg 18
0-60mph 5.3 secs
Top speed 162mph
Price new £27,950 (1979)
Price now £70-350,000*

Porsche 911 (964) turbo 3.6

Sold/number built 1991-’93/5097 (all)
Construction steel monocoque
Engine all-alloy, sohc-per-bank 3600cc flat-six, turbocharger, intercooler and Bosch K-Jetronic fuel injection
Max power 355bhp @ 5500rpm
Max torque 384lb ft @ 4200rpm
Transmission five-speed manual, RWD via LSD
Suspension independent, at front by MacPherson struts rear semi-trailing arms, coil springs, telescopic dampers; anti-roll bar f/r
Steering power-assisted rack and pinion
Brakes discs, with servo and ABS
Length 14ft ¼in (4275mm)
Width 5ft 10in (1775mm)
Height 4ft 3in (1308mm)
Wheelbase 7ft 5in (2272mm)
Weight 3241lb (1470kg)
Mpg 21
0-60mph 4.7 secs
Top speed 174mph
Price new £72,294 (1992)
Price now £70-325,000*

Porsche 911 (993) turbo

Sold/number built 1995-’98/5978
Construction steel monocoque
Engine all-alloy, sohc-per-bank 3600cc flat-six, twin turbochargers, twin intercoolers and Bosch DME sequential fuel injection
Max power 402bhp @ 5750rpm
Max torque 398lb ft @ 4500rpm
Transmission six-speed manual, 4WD
Suspension independent, at front by MacPherson struts rear multi-link, coil springs, telescopic dampers; anti-roll bar f/r
Steering power-assisted rack and pinion
Brakes discs, with servo and ABS
Length 13ft 11in (4245mm)
Width 5ft 11in (1795mm)
Height 4ft 3in (1285mm)
Wheelbase 7ft 5in (2272mm)
Weight 3307lb (1500kg)
Mpg 18
0-60mph 4.3 secs
Top speed 180mph
Price new £97,950 (1996)
Price now £100-235,000*