Guide: Porsche 911 3.6 Turbo (964)
Background
Between 1975 and 1989, Porsche’s 911 Turbo (internal type code 930) offered performance to rival production models from Ferrari and Lamborghini albeit in a package that was practical enough for daily use. The Porsche also cost substantially less than a Ferrari BB, Testarossa or Lamborghini Countach, and despite a reputation for sometimes unpredictable handling, 911 Turbos sold by the bucket load.
By the time production of the G-body 911 ended, just under 20,000 930s had been produced. This was a far cry from the 400 units Porsche had originally expected to produce in order to homologate a pair of forced induction racing cars for the 1976 season (the 934 and 935). As it happened, the 911 Turbo proved so popular that it became a permanent fixture in the Porsche model line up and an instant automotive icon.
Between 1988 and 1989, the G-body 911 (which in normally aspirated trim had been built in 3.2-litre form since 1984) was phased out in favour of the heavily revised 3.6-litre 964 variant which initially arrived in four-wheel drive Carrera 4 trim in late 1988 (for the 1989 model year). For the 1990 model year, the G-body 911 was discontinued entirely as the 964 became available in rear-wheel drive Carrera 2 trim. Targa and Cabriolet body styles were also added to the range.
As for the Turbo, production of a forced induction 964 did not begin until September 1990 for the 1991 model year. However, instead of a turbocharged version of the 964’s heavily revised Type M64 power unit, this latest 911 Turbo ran an uprated version of the old Type 930 motor that had been used since 1982 (dubbed Type M30/69).
Although the 964 Turbo was very well received, it arrived at a time when Porsche was in the early stages of a financial meltdown that nearly resulted in bankruptcy. Inefficient manufacturing techniques, poor trading conditions and an outdated range saw sales figures tumble during the first half of the 1990s.
It was in the midst of this crisis that arguably the most highly rated production version of the 911 Turbo emerged.
Porsche unveiled the new 911 3.6 Turbo at a press event in France on February 12th 1993. Like its predecessor, this latest machine would be offered exclusively as a Coupe. It featured a highly anticipated turbocharged version of the twin spark 964 engine which provided a load of extra horses, gobs more torque and a much flatter power curve.
Significantly, it would be the last series production 911 Turbo with rear-wheel drive as it was already known the car’s successor would be an all-wheel drive machine.
Engine / Gearbox
As expected, the most significant difference between the existing 964 Turbo and this latest iteration was what featured in the engine bay.
The new Type M64/50 engine was another all-alloy power unit that employed single overhead camshafts, two valves per cylinder and dry-sump lubrication. Significantly, it now shared the same crankshafts, connecting rods, crankcases and cylinder heads with the rest of the 964 range.
Differences to the normally aspirated 964 engine included new pistons, high-lift camshafts, a reduced 7.5:1 compression ratio (down from 11.3:1) and single instead of twin-plug ignition. There was also an LuK flywheel, an uprated oil cooler, the latest Bosch DME engine management and a repositioned oil tank (moved to in front of the rear axle to allow more room for a bigger silencer).
A KKK K27 turbocharger and associated plumbing (to include the intercooler) was imported from the outgoing model, but for this latest application the turbo pressure was cranked to 0.85 bar (up from 0.7) and full boost now came on stream at 3500rpm.
Displacement was identical to the rest of the 964 range: 3600cc thanks to a bore and stroke of 100mm and 76.4mm respectively. These figures represented gains of 3mm and 2mm for an overall increase of 301cc when compared to the old 3.3-litre motor.
Peak output was 355bhp at 5500rpm and 382lb-ft at 4200rpm. Significantly, off-boost performance was much-improved.
For comparison, the outgoing model had pumped out 320bhp at 5750rpm and 347lb-ft at 4500rpm.
Transmission was through the existing G50/52 five-speed manual gearbox (with revised ratios), a single-plate clutch and a Carrera RS rear axle with 20% locking limited-slip differential.
Chassis
As per its predecessor, this latest Turbo was based on the rear-wheel drive 964 Carrera 2’s steel bodyshell.
The previously optional Sport suspension (code M030) was fitted as standard (apart from to North American-bound cars where a taller ride height was mandated). The M030 kit included shorter springs and stiffer dampers that resulted in a 20mm lower than normal ride height.
The 3.6 Turbo (like every 964) used a different suspension arrangement than the old G-body 911 – gone was the old torsion bar arrangement in favour of coil sprung dampers. A MacPherson strut arrangement was retained at the front while the back end used the cast-aluminium semi-trailing arms originally seen with the 930. Anti-roll bars were fitted at either end.
Like the Carrera RS and Turbo S Lightweight, the 3.6 Turbo used cross-drilled and ventilated discs of 322mm up front and 299mm at the back. The Anti-lock Brake System was similarly re-calibrated compared to regular the 964 and a hydraulic instead of vacuum servo was fitted along with a bigger master cylinder.
In a similar fashion to the Turbo S Lightweight, the brake calipers were painted red as standard.
Handsome three-piece Speedline wheels were also imported from the Turbo S Lightweight. They measured 18x 8-inches at the front, 18 x 10-inches at the rear and were originally shod with Yokohama A-008P tyres.
As before, a 77-litre fuel tank was installed underneath the front lid.
Bodywork
Other than a ‘turbo 3.6’ script on the engine lid and a Turbo S Lightweight-style rear bumper, the new car was identical to the outgoing 3.3-litre forced induction 964.
Thanks to its pumped up appearance (a result of the dramatically widened fenders) and massive fixed rear spoilers, the Turbo appeared much more aggressively-styled then its narrow-bodied normally aspirated cousins.
Like the rest of the 964 range, these latest generation 911s were characterised by their one-piece bumpers fabricated from deformable thermoplastic and mounted on aluminium subframes (or telescopic dampers in the case of American-spec. examples). The 964 had also adopted a new tail light arrangement, extended fibreglass sill covers down each flank, a low profile rubber for the windscreen surround and smaller drip rails to improve aerodynamics. Similarly, the rear windscreen was more neatly integrated and the underbody had been made smoother.
Interior
Inside, other than airbags now having been fitted as standard along with an updated air-conditioning system, nothing much had changed; while the 964’s exterior modifications had been quite dramatic, the cockpit fixtures harked back to the early 1970s.
The seats, instrument binnacle, dash and door panels were all imported from the old 3.2 Carrera / 930.
The familiar five gauge instrument layout comprised a central tachometer with analogue boost gauge 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 previous model, there were some extra warning lights and subtle revisions to the instrumentation (which was now back lit).
Air-conditioning, electric windows and electric mirrors were standard along with an onboard computer that featured a digital boost indicator.
Options
Porsche offered a vast array of optional extras to include coloured wheel centres, titanium or black brake calipers, polished wheels, a sunroof, a long-range 92-litre fuel tank, ruched leather, an extended centre console, Sports seats, heated seats, eight-way electric seats, a choice of audio systems, mobile phone preparation, wooden or aluminium cockpit inserts and extended leather.
Out of range exterior and interior colours could be ordered via Porsche Exclusive.
X88 Power Kit
Another optional extra was a Power Kit (option code X88).
The Power Kit comprised a special Type M64/50S engine that came with uprated cylinder head inlet and exhaust ports, a modified inlet manifold and spacer flanges, high-lift camshafts, an improved oil cooler, a larger version of the KKK K27 turbocharger with more efficient intercooler, uprated valve timing, uprated fuel injectors and four outlet exhaust system.
The flywheel and clutch were also new and a 40% self-locking differential was fitted instead of the standard 20% version. Front and rear shock mounts were reinforced.
Peak output was 380bhp at 5750rpm and 384lb-ft at 5000rpm (up from 355bhp at 5500rpm and 382lb-ft at 4200rpm).
Weight / Performance
At 1470kg the 3.6-litre 964 Turbo weighed the same as the outgoing 3.3-litre version.
Top speed went from 169mph to 175mph while the 0-62mph time dropped from 5 seconds to 4.7 seconds.
End of Production
Porsche officially ended production of the 911 Turbo 3.6 in September 1993 when the new 993-based 911 was introduced.
By this stage, 1407 cars are believed to have been completed of which 147 were right-hand drive.
However, that was not quite the end of the story as Porsche had an additional 93 chassis left over which were subsequently sent to the Exclusive department where they were assembled to Turbo S specification.
911 3.6 Turbo S
The 964 3.6 Turbo S was built by Porsche Exclusive between September 1993 and February 1994.
Of the 93 examples completed, 76 were finished to Flachbau trim (covered separately) while the remaining 17 were configured with the 911’s standard headlight arrangement. All 17 of these cars were dispatched to the North American market. They cost 20% more than the outgoing non-S model while the Flachbau variants were priced at a massive 60% premium.
In addition to the X88 power kit, each Turbo S came with a special front lip spoiler (X92), a body coloured rear spoiler (X83), air inlets in the rear fenders (X99) and polished wheels (407). Both the rear spoiler and rear fender inlets had previously been seen on the 3.3-litre Turbo S Lightweight.
Text copyright: Supercar Nostalgia
Photo copyright: Porsche - https://www.porsche.com
