Guide: Porsche 911 3.6 Carrera (964)
Background
When the 911 arrived in 1964, it was a significant step up in price over the 356 that had served Porsche so well since 1948. However, buyers flocked to the new model and the 911 quickly became a best seller thanks to its styling, performance, practicality and build quality.
During the 911’s early years, its Flat 6 engine was enlarged from 2.0 to 2.2 and then 2.4-litres. A 2.7-litre unit was subsequently plumbed into the Carrera RS prior to the 911’s first major revamp which took place for the 1974 model year. At this point, impact-absorbing bumpers were added in a bid to meet tightening safety legislation.
Although Porsche management thought the 911 would ultimately be replaced by the front-engined 928 in the late 1970s, this idea was abandoned when Peter Schutz took over from Ernst Fuhrmann as the company’s Chairman in 1980.
Soon after the decision was made to retain the 911, the slightly down on power engines it had been fitted with since the mid 1970s were replaced with a more potent 3.2-litre unit.
Around this time, work began on the firm’s next major 911 revamp. Porsche claimed the resultant machine was 87% new and thus gave it a new type number: 964.
The 964 was launched at the Frankfurt Motor Show in September 1988. Production began in January 1989.
First to arrive was the four-wheel drive 964 Carrera 4 Coupe. In August 1989, Targa and Cabriolet body styles were added to the range along with a rear-wheel drive variant: the Carrera 2. At the same time, Porsche introduced a new semi-automatic Tiptronic gearbox option.
Because highly visible parts such as the roof, glass, doors, hood and front wings had been imported from the outgoing model, the 964 looked to be little more than a facelifted 911. However, under the skin, the suspension, brakes, engine and transmission were substantially modified.
Chassis
Size-wise, the 964’s hot zinc-dipped steel bodyshell was almost identical to its predecessor. Changes included a new underbody complete with centre tunnel for a torque tube.
The luggage compartment was re-shaped and reduced in size to accommodate the front differential and driveshaft assemblies for the four-wheel drive system. This also meant fuel tank capacity had to be reduced from 85-litres to 77-litres.
A new heating and ventilation system was long overdue and finally brought the 911 up to modern standards.
The revised suspension arrangement did away with torsion bars in favour of coil springs with Boge dampers. A MacPherson strut arrangement was retained at the front while the back end used the cast-aluminium semi-trailing arms from the 930. The front anti-roll bar was enlarged from a 20mm diameter to 22mm. At the rear, it was reduced from 21mm to 20mm.
Overall, this reworked suspension configuration improved handling and ride quality and lessened road noise.
Other refinements included power steering and ABS, neither of which had been fitted to the 911 before.
The brake system itself was largely imported from the 928 S4. The ventilated discs had a 298mm diameter at the front and 299mm diameter at the rear. Four-piston aluminium calipers were installed all round.
To replace the long-serving Fuchs wheels, new seven-hole rims broadly similar to those used on the 928 S4 Club Sport were introduced. As per the outgoing 1989 model year 911 3.2, the wheels measured 16 x 6-inches at the front and 16 x 8-inches at the rear.
The new rims were originally shod with Bridgestone tyres.
Engine & Gearbox
In the engine bay was a quieter, more powerful Flat 6 that was suitable for all markets and could run on lower grade fuel (95 RON instead of 98 RON). It was though a step up in complexity compared to the outgoing 3.2-litre unit.
The Type M64/01 engine was another all-alloy power unit that employed single overhead camshafts, two valves per cylinder and dry-sump lubrication.
It was bored from 95mm to 100mm and stroked from 74.4mm to 76.4mm. This gave an overall displacement of 3600cc which represented a gain of 436cc.
New ceramic port liners reduced cylinder head temperatures and allowed the sodium-cooled exhaust valves to be replaced with hollow valves. Sodium cooling was now used on the intake valves instead. This enabled heat to transfer from the head to the valves, helped cold starting and reduced noise.
Other new equipment included forged pistons with dished crowns, a revised crankcase and lightweight crankshaft.
A new twelve-blade cooling fan was driven at the same ratio as on the 959.
The cam timing chain tensioners were redesigned and a new twin spark ignition system with dual distributors was also introduced.
The intake system was completely revised and a free-flow catalytic converter was standard on all cars.
Porsche employed the latest Bosch Motronic engine management software and upped the compression ratio from 10.3:1 to 11.3:1.
Peak output was 250bhp at 6100rpm and 229lb-ft at 4800rpm. This compared favourably to 231bhp at 5900rpm and 210lb-ft at 4800rpm for the outgoing 3.2-litre un-catalysed engine.
The 964 Carrera 4 was the first all-wheel drive 911 offered to the public. A prototype 4x4 Studie had been shown as far back as 1981 which was followed by the Paris-Dakar Rally winning 953 of 1984. The 953 had itself served as a test-bed for the 959 which then won the Dakar in 1986.
The system adopted for the 964 was more akin to the comparatively straightforward 953 as opposed to the complex approach taken by the 959.
It used three differentials plus a multi-plate clutch. The centre differential normally sent 31% of the torque to the front axle and 69% to the rear. The clutch incorporated with the centre differential intervened whenever the ABS sensors detected a loss of traction at the rear wheels and sent more torque to the front.
The rear differential also incorporated a similar clutch that acted as a limited-slip differential controlled by the ABS system.
In extreme conditions, both the centre and rear differentials could be manually locked via a toggle switch ahead of the gear lever. The differential locks would automatically disengage at over 25mph.
The lightweight five-speed gearbox was given type number G64/00.
Bodywork
Porsche re-styled the 964 to freshen it up for the curve-conscious 1990s. The changes also improved aerodynamics.
Most obviously new were one-piece bumpers fabricated from deformable thermoplastic and mounted on aluminium subframes (or telescopic dampers in the case of American-spec. examples).
There was also a new tail light arrangement and the rear fenders were subtly re-profiled.
The single pipe exhaust now exited from under the right-hand side instead of the left-hand side of the back bumper.
One of the most attention-grabbing features was a retractable rear spoiler that lifted electronically upwards at 80kmh / 50mph. It automatically lowered once road speed dropped below 10kmh / 6mph. As the rear spoiler was housed in a larger opening on the engine cover, cooling was also improved.
Extended fibreglass sill covers were mounted down each flank and tidied up the side profile.
To further improve airflow, the front windscreen used lower profile rubber and the drip rails either side were reduced in size. Similarly, the rear windscreen was more neatly integrated and the underbody was made smoother.
Interior
The area that came in for least attention on the 964 was the interior. The seats, instrument binnacle, dash and door panels were all imported from the outgoing model.
The familiar five gauge instrument layout comprised a central tachometer flanked to the right by a speedometer and clock. To the left were combined instruments for oil pressure / oil temperature and fuel / oil level.
Although the basic dash architecture was carried over from the 3.2-litre Carrera, there were subtle revisions to the instrumentation (which was now back lit) and some extra warning lights.
Among the other new features was a raised 959-style central driveshaft tunnel for the four-wheel drive system. Ahead of the gear lever were a trio of switches and controls for the differential locks.
There was also a new footrest positioned next to the clutch pedal.
As a result of the new heating and ventilation system, climate control switchgear from the 944 was imported and housed in the middle of the dash.
Options
Optional upgrades included air-conditioning, an electric sunroof (with new wind deflector), Sports seats, heated seats, twelve-way electric seats, full leather upholstery and a choice of audio systems.
Weight / Performance
Porsche quoted a weight of 1450kg, a top speed of 158mph and 0-62mph time of 5.8 seconds.
For comparison, the original 1984 model year 911 3.2 Carrera Coupe weighed 1160kg, had a top speed of 150mph and 0-62mph time of 5.6 seconds.
1989 Model Year K-series Production
Porsche closed out the 1989 model year by setting an all-time high for 911 production with a figure of 18,841 units across the entire range.
That number comprised 3185 of the new K-series 964 Carrera 4 Coupes, 12,914 of the outgoing 3.2-litre Carreras and 2742 Turbos.
1990 Model Year L-series
For the 1990 model year, only the L-series 964 was offered as the 3.2-litre Carrera was discontinued along with the Turbo. A turbocharged version of the 964 would not be introduced until the 1991 model year.
The big news for the 1990 model year L-series 964 (produced from August 1989) was the availability of Cabriolet and Targa body styles. For the first time, the Cabriolet came with an electric folding roof as standard. Both Cabriolet and Targa variants weighed 50kg more than the Coupe.
Updates made across the board included a dual mass flywheel with rubber damper to reduce vibration, headlight height adjustment and a centre console switch that allowed the rear spoiler to be raised and lowered from the cockpit.
A ten-speaker stereo and onboard computer were added to the options list.
Carrera 2
In October 1989, Porsche introduced the rear-wheel drive Carrera 2. It came with a simpler, lighter transmission including a new G50/03 gearbox.
As a result, the Carrera 2 tipped the scales at 100kg less than the Carrera 4. Acceleration times and top speed were officially unchanged. A limited-slip differential was offered as an optional extra.
Tiptronic
At the same time, Porsche launched their four-speed Tiptronic gearbox which was the first semi-automatic transmission offered by a major car maker. Available only on the Carrera 2, Tiptronic was a collaboration between Porsche, ZF and Bosch. It offered both fully automatic and sequential manual shifting.
The automatic mode had five different programmes to suit different driving styles; a computer would select the most appropriate mode according to driving style.
A manual setting enabled the driver to shift up or down by pushing the gear lever forwards or backwards respectively.
When Tiptronic was specified, a smaller 19mm rear anti-roll bar was installed (instead of the standard 20mm item). Acceleration times were much slower; 0-62mph took 6.6 seconds instead of 5.8.
Tiptronic 911s also came with an onboard computer that provided a variety of information to include journey time and distance, daily distance, remaining fuel, average fuel consumption, a digital speed read out, average journey speed and outside temperature.
During the 1990 model year, 7524 L-series 964s were made. This number comprised 5354 Coupes, 1629 Cabriolets and 541 Targas. Such figures were obviously a big drop compared to the near 19,000 examples of the 911 that had rolled out of the factory the year before.
1991 Model Year M-series
For the 1991 model year M-series 964 (production of which began in August 1990), Porsche made a number of minor updates.
An interior light delay switch was introduced on all models along with new seat back release buttons and a new control unit for the central locking.
The manual gearbox ratios were altered slightly and a Sports suspension option was offered for the Carrera 2. The Sports suspension pack comprised new shocks, stiffer springs and a thicker front anti-roll bar.
Driver and passenger airbags were introduced for some left-hand drive markets before all left-hand drive 964s were equipped as such from April 1991.
17,483 normally aspirated 964s were built during the 1991 model year in addition to 2942 of the new Turbos which went some way tor redress the big drop twelve months prior. Production was splits thus: 9448 Coupes, 6093 Cabriolets and 1942 Targas.
1992 Model Year N-series
The 1992 model year N-series 964 was built from August 1991. Five-spoke Cup Design wheels and teardrop mirrors became standard equipment and more warning lights were added to the dash.
In addition to the new Carrera RS and RS America (covered separately), Porsche also introduced the Turbo Look option. Only available on the Carrera 2 Coupe and Carrera 2 Cabriolet, the Turbo Look pack comprised the Turbo’s wide bodywork along with its bigger brakes, stiffer suspension, thicker anti-roll bars and wider wheels / tyres.
Three special Turbo Look colour schemes were offered: Raspberry Red Metallic with a Red interior, Wimbledon Green Metallic with a Green interior and Lavender Blue Metallic with a Grey interior. Turbo Look Cabriolets sold in the USA were dubbed America Roadsters.
Having manufactured nearly 20,500 911s in various iterations the previous year, production dropped to under 14,000 for the 1992 model year.
10,244 of these were regular 964s, 2051 were the new Carrera RS and 298 were RS Americas. There were also 1225 Turbos in various iterations. Production of the regular 964 was split as follows: 5559 Coupes, 3877 Cabriolets and 808 Targas.
1993 Model Year P-series
The 1993 model year P-series 964 arrived in August 1992. The only changes of note saw a VIN now located on the A pillar so it could be seen from outside and airbags for right-hand drive cars.
The long-range 92-litre fuel tank from the Carrera RS was added to the options list for the Carrera 2.
Speedster
In October 1992, Porsche unveiled the latest incarnation of their much-loved Speedster body style.
Production of the 964 Speedster began in February 1993 and a run of 3000 cars was anticipated.
Based on the narrow-bodied Carrera 2 Cabriolet, each Speedster was fitted with a cut-down windscreen and body-coloured glassfibre moulding behind the seats. Porsche supplied a simplified hood which was only recommended for emergency use.
Other equipment included the leather-trimmed Recaro bucket seats, simplified door panels and rear seat delete from the Carrera RS. The seat backs, door pull chords, gear gaiter, handbrake gaiter and instrument surround were colour coded to match the bodywork.
All Speedsters came with manual teardrop wing mirrors.
Optional extras included Sports seats from the standard car (which could also be heated), a Tiptronic gearbox and body coloured wheels.
Carrera 4 Celebration
In March 1993, another special edition was introduced, this time to mark 30 years of 911 production.
The Carrera 4 Celebration featured wide Turbo-style bodywork but none of the other Turbo Look goodies. It could be identified on account of its stylised 911 script on the engine lid (underlined with 30 Jahre text). Full leather upholstery was fitted along with the long-range 92-litre fuel tank from the Carrera RS.
In total, 911 were built.
March 1993 also saw a further uprated 3.8-litre Carrera RS added to the range (covered separately). Only 55 were built in order to homologate an RSR variant for GT racing.
Towards the end of the 1993 model year, a number of right-hand drive 964 Targas (which had proved difficult to sell) were taken to Porsche’s Exclusive department. They were kitted out with embossed leather trim and the Targa roll hoop was given a ‘Florio’ script. How many were built is unknown.
End of Production
Unfortunately, 1993 turned out to be Porsche’s nadir.
With just 9230 911s built in total, production was less than half what it had been two years prior.
This figure looked even worse when the hugely disappointing sales of the 968 were factored in.
The result was a record loss for the company.
Of the 9230 911s manufactured for the 1993 model year, 7774 were normal 964s, 518 were RS Americas and 938 were Turbos.
In terms of the regular 964s, 4049 were Coupes, 2152 were Cabriolets, 637 were Targas and 936 were Speedsters.
Fortunately, with the arrival of the revamped 993, Porsche began to turn a corner. When the all-new 986 Boxster arrived a couple of years later, the firm’s recovery was in full swing.
Text copyright: Supercar Nostalgia
Photo copyright: Porsche - https://www.porsche.com
