Porsche 964, Frequently Asked Questions

Buying

Should I buy a Carrera 2 or a Carrera 4?

The Carrera 2, almost always. The C2 is lighter by approximately 75 kg, has more communicative steering, and is simpler to maintain. The C4’s AWD system was the first fitted to a 911 and is complex, with known issues around the aluminium wiring in the control unit and the transfer case requiring periodic specialist attention. The C4 is more secure in heavy rain, but in Australian conditions where most driving is on dry tarmac, the C2’s lighter weight and purer handling make it the better driver’s car. The C2 also holds its value better and is more sought after by collectors. The only strong argument for the C4 is if you regularly drive in genuinely poor conditions or simply prefer the added security.

Is every 964 going to leak oil?

Yes. Without exception. The M64 air-cooled flat-six is a hot engine in a tight engine bay with multiple gasket faces, dissimilar metals expanding at different rates, and seals that degrade with thermal cycling. The question is not whether a 964 leaks oil, but how much and from where.

A light film of oil on the engine’s lower surfaces is normal and acceptable. Active dripping from the chain tensioner housings, cam covers, or cylinder base gaskets needs attention. Oil contacting the exhaust manifolds or heat exchangers is a fire risk and must be addressed immediately. When inspecting a 964, get it on a hoist and assess the oil situation honestly. A freshly steam-cleaned engine bay on a car being sold should raise suspicion rather than inspire confidence.

What is the best model year 964 to buy?

The 1992-1993 Carrera 2 is the sweet spot. By 1992, Porsche had addressed the early chain tensioner issues with updated components, the engine management had received incremental refinements, and the minor production-line issues of the first two years had been resolved. A 1992 or 1993 C2 coupe with a manual gearbox, documented service history, and evidence of the chain tensioner update is the ideal buy.

That said, a well-maintained 1989 or 1990 car with updated tensioners is every bit as good to drive. Do not dismiss an early car simply because of its model year, the car’s individual maintenance history matters more than the year of production.

How important is service history?

It is the single most important factor after the car’s physical condition. A 964 with a complete service history from a reputable Porsche specialist, documenting oil changes every 5,000-8,000 km, valve adjustments at the correct intervals, and all major service items, is worth 15-25% more than an identical car with gaps in its records. More importantly, a documented service history dramatically reduces the risk of hidden mechanical problems. An undocumented 964 is a gamble, and the stakes are high.

What should I budget beyond the purchase price?

For the first year of ownership, budget $10,000-$20,000 AUD above the purchase price for a comprehensive baseline service, any deferred maintenance identified during the pre-purchase inspection, and the inevitable items that reveal themselves in the first few thousand kilometres. Even a well-maintained 964 will need attention when it changes hands, the new owner’s specialist will always find things the previous owner’s specialist did not address.

Ongoing annual costs are $5,000-$10,000 for a car driven 5,000-10,000 km per year, covering insurance, servicing, tyres, and the contingency fund for unexpected repairs.

Does the 964 have an IMS bearing problem?

No. The IMS (intermediate shaft) bearing issue affects the water-cooled 996 and 997 generation 911s, not the 964. The 964’s M64 engine does not have an intermediate shaft. The timing chain drives the camshafts directly. This is a common confusion, and if a seller mentions “IMS bearing” in relation to a 964, they do not understand the car they are selling.

Driving and Ownership

Can I daily drive a 964?

Yes, and many owners do. The 964 was specifically designed to be a more usable 911 than its predecessors. Power steering, ABS, airbags, a functioning heater, and reasonable luggage space (the front boot holds a weekend bag, and the rear seats fold to provide additional storage) make the 964 a practical proposition for daily use.

The caveats are real, however. The car is 30+ years old, and every ancillary component (window regulators, air conditioning, door locks, electrical switches) is ageing. Daily use accelerates wear on these items. The ride quality, while good by 911 standards, is firm by modern standards. There is no traction control (aside from the C4’s AWD). The engine requires premium 98 RON fuel. Insurance is more expensive than a modern car. And parking a $150,000+ classic in a shopping centre car park takes nerve.

For a weekend driver, club car, or second car for enjoyable commuting, the 964 is superb. As a sole daily driver covering high kilometres in city traffic, it is possible but demanding.

What does the 964 feel like to drive?

The 964 feels like a 911 should feel. The engine sits behind you, and you can feel its mass shifting as you turn. The steering is precise and communicative, even with the power assistance (which is well-calibrated and not numb). The gearbox, the G50 5-speed, has a precise if slightly notchy shift action that rewards deliberate inputs. The brakes are strong. The ride is taut but not harsh.

The engine is the star. The 3.6-litre flat-six revs with a mechanical urgency that water-cooled engines do not replicate. The sound builds from a bass rumble at idle through a hard-edged bark in the mid-range to a wail approaching the 6,800 rpm redline. There are 250 hp, which does not sound like much by modern standards, but the car weighs 1,350 kg and the power delivery is immediate and linear. It feels faster than the numbers suggest.

The rear-engined handling requires respect. The 964 is more forgiving than earlier 911s, but it will still oversteer suddenly if you lift off the throttle aggressively mid-corner. Learn to drive it smoothly, trail-brake into corners, and feed the power on progressively, and the 964 rewards you with a balance and adjustability that few modern cars can match.

What fuel should I use?

98 RON premium unleaded. The M64 engine has a compression ratio of 11.3:1 and is tuned for high-octane fuel. Running 95 RON is possible in an emergency but not recommended for sustained use, the DME engine management will retard the ignition timing to prevent detonation, but this reduces power and increases thermal stress. E10 ethanol-blended fuel is acceptable if it is 98 RON.

What oil does the 964 need?

The air-cooled flat-six relies on its oil for both lubrication and a significant portion of its cooling. Oil quality and viscosity are critical.

The recommended oil is a high-quality 15W-50 or 10W-60 semi-synthetic or full synthetic meeting Porsche’s A40 specification. Mobil 1 15W-50, Motul 300V 15W-50, and Castrol Edge 10W-60 are popular choices among Porsche specialists. The engine holds approximately 11.5 litres with filter change.

Change the oil every 5,000-8,000 km or annually, whichever comes first. Do not extend oil change intervals, the oil is doing more work in an air-cooled engine than in a water-cooled one, and it degrades faster.

Maintenance

How often should the 964 be serviced?

Minor service (oil, filter, visual inspection): every 5,000-8,000 km or annually.

Intermediate service (oil, filters, valve adjustment check, brake inspection, fluid levels): every 15,000-20,000 km or every 2 years.

Major service (all fluids, valve adjustment, distributor drive belt, comprehensive inspection): every 30,000-40,000 km or every 4 years.

Brake fluid: every 2 years regardless of mileage.

Gearbox oil: every 40,000-60,000 km.

How much does a 964 service cost?

An annual minor service (oil, filter, inspection) at a Porsche specialist costs $1,200-$2,000 AUD. A major service (30,000 km interval) costs $3,000-$6,000. Specialist labour rates are typically $150-$220 per hour.

These costs assume a healthy car with no deferred maintenance. If the car has been neglected, the first comprehensive service can easily exceed $10,000 as accumulated issues are addressed.

What is the valve adjustment, and how often is it needed?

The 964’s M64 engine uses hydraulic valve lifters, which means the valve clearance is self-adjusting. Unlike the earlier air-cooled 911 engines (which required manual valve adjustment every 15,000 km), the 964 does not need periodic valve clearance checks. This is a significant maintenance advantage over the older cars.

However, the hydraulic lifters can develop a ticking noise, particularly on cold start-up, if the engine oil is degraded or the oil level is low. If you hear persistent lifter tick, check the oil level and condition first. If the ticking continues with fresh oil at the correct level, the hydraulic lifters may need replacement (an engine-out job on some cylinders).

Does the 964 have a timing belt or a timing chain?

A timing chain. The M64 engine uses a duplex (dual-row) roller chain to drive the camshafts. There is no timing belt to replace. The chain itself is durable and typically lasts the life of the engine. The concern is not the chain itself but the chain tensioner guides, which keep the chain taut. Early cars had weaker tensioner guides that could fail (see the common problems guide). The tensioner guides are the service item, not the chain.

The 964 does have a toothed rubber belt that drives the dual distributors. This belt is often overlooked but should be replaced every 5-6 years.

What is the chain tensioner update, and has my car had it?

The early 964 engines (approximately 1989-1991) used hydraulic chain tensioner guides made of a material that could become brittle and fail with age. Porsche released updated tensioner components that are more durable. The update involves removing the engine and replacing the tensioner guides (and typically the chain and sprockets at the same time).

To determine whether your car has had the update, check the service records for a chain tensioner service. A specialist can also inspect the tensioners with the engine in the car (via a small inspection port), though a definitive assessment usually requires engine removal. If there is no documentation and the car is an early model, assume the update has not been done and budget accordingly.

Technical

What is the difference between the 3.3 Turbo and the 3.6 Turbo?

These are fundamentally different engines. The 3.3 Turbo (M30/69) is an evolution of the engine that powered the 930 Turbo from 1978, a 3,299 cc single-turbocharged flat-six producing 320 hp. It has pronounced turbo lag and a dramatic power delivery.

The 3.6 Turbo (M64/50) is based on the standard Carrera’s M64 engine, bored and stroked to 3,600 cc with a single KKK turbocharger. It produces 360 hp and 520 Nm of torque with significantly less lag and a more progressive power delivery than the 3.3. The 3.6 Turbo is the better engine in every measurable respect: more power, better response, greater refinement. It is also considerably rarer (approximately 1,437 units versus approximately 3,660 units for the 3.3) and more valuable.

What is the difference between a 964 RS, RS Touring, RS 3.8, and RS America?

964 RS: The full-fat European homologation car. 260 hp, fully stripped interior, thinner glass, stiffened suspension, approximately 1,220 kg. The most raw and focused 964.

RS Touring: An RS with some comfort features reinstated (carpet, electric windows, air conditioning option). Same engine and suspension as the RS, but approximately 50 kg heavier. A more liveable alternative for those who wanted the RS experience without the spartan interior.

RS 3.8: A limited-production variant with a 3,746 cc engine producing approximately 300 hp, the Turbo body (wide guards), and further chassis modifications. Extremely rare (approximately 55 units) and extremely valuable.

RS America: A US-market lightweight variant based on the standard Carrera 2. Standard 250 hp engine (not the RS’s 260 hp unit), simplified interior (no sunroof, no rear seats, manual windows, limited colour choices), and standard suspension (though stiffer than the base Carrera). The RS America is a lighter, more focused Carrera rather than a true RS.

How much does an engine rebuild cost?

A comprehensive engine rebuild on a 964 M64 engine costs $25,000-$45,000 AUD at a reputable specialist. This includes stripping the engine, inspecting and measuring all components, replacing all seals and gaskets, reconditioning or replacing the cylinders and pistons, machining the crankshaft journals, replacing the main and rod bearings, updating the chain tensioners, and reassembling to factory specifications with new hardware throughout.

A top-end rebuild (cylinders, pistons, head work) without splitting the crankcase is $12,000-$20,000. A reseal only (all gaskets and seals without replacing major internal components) is $6,000-$12,000.

The specialist you choose matters enormously. An engine rebuilt by a reputable Porsche air-cooled specialist (there are several in Australia who specialise exclusively in 911 engines) will outlast and outperform one rebuilt by a general workshop. Ask for references, inspect their work, and do not choose based on price alone.

Is the 964 a classic 911 or a modern 911?

This is one of the great debates in the Porsche community, and the honest answer is that the 964 is both. It is the last generation to use air cooling, a rear-engine layout with no electronic stability aids, and analogue instrumentation, all hallmarks of the classic 911. But it is also the first 911 with coil springs, power steering, ABS, and electronic engine management, features that define the modern era.

In practical terms, the 964 drives like a classic 911 that has been made competent. The steering communicates like an older car. The engine sounds like a mechanical device rather than a refined appliance. The handling demands attention and rewards skill. But you can also drive it confidently in traffic, in the rain, and on long journeys without the constant vigilance that an earlier 911 demands.

For many enthusiasts, this combination of classic character and modern capability is exactly what makes the 964 special. It is the bridge between two eras, and it captures the best of both.

How does the 964 compare to the 993?

The 993 (1994-1998) is the 964’s direct successor and the final air-cooled 911. The 993 improved on the 964 in almost every measurable way: the multi-link rear suspension provides better grip and more predictable handling at the limit, the VarioRam intake system lifts power to 272 hp, the body is sleeker and more aerodynamically refined, and the interior is noticeably more modern.

The 993 is the better car. The 964 is the more characterful car. The 993 is smoother, more composed, and more capable. The 964 is rawer, more communicative, and more demanding. The 993 flatters the driver. The 964 challenges the driver.

The choice between them is personal. The 993 commands a 30-50% premium over an equivalent 964, so the decision often comes down to budget as well as preference. Many enthusiasts start with a 964 and either fall in love with its character and stay, or upgrade to a 993 once they have confirmed that the air-cooled 911 experience is what they want.