REFERENCE / PORSCHE FACTORY BOOKLET
1973 911 S.
Factory specifications.
Oil capacity. Fuchs wheels. Engine dimensions. Find the figure, then follow the explanation.
Frequently looked up.
This reference draws on Porsche’s Technical Specifications: Models, Dimensions, Tolerances, first English edition, current as of 31 May 1973. The figures below follow the 911 S and 1973-model columns.
For the story of this particular car, visit the owner’s archive. For what has been renewed, explore the service history.
OIL CHANGE / US QUARTS & LITRES
How much oil does a 1973 Porsche 911 S take?
10.6 US quarts Approximately 10 litres per oil change.
Porsche’s factory booklet gives an approximate oil-change quantity of 10 litres for the 1973 911 S. Converted to US liquid quarts, that is about 10.6 quarts.
Why does this engine carry so much oil?
Oil change versus total capacity
The same table lists 11–13 litres for the manual-transmission S’s total oil system at the dipstick minimum and maximum. Oil remains in parts of the dry-sump system during a normal change, so those larger figures are not the refill quantity.
Use the approximate change quantity as a reference and establish the final level with the dipstick, on level ground with the engine idling at operating temperature. Avoid filling to a total-capacity figure.
Factory capacities · printed pages 104–105
1973 owner’s manual · oil-level instructions
Engine
2.4-litre flat-six engine specs.
The dimensions behind the badge: an 84 mm bore and 70.4 mm stroke give the 2.4 its exact capacity. A separate oil tank and a front oil cooler complement the engine’s air cooling.
Factory booklet · printed pages 12–21| Configuration | Six horizontally opposed cylinders |
|---|---|
| Displacement | 2,341 cm³Marketed as 2.4 litres. |
| Bore × stroke | 84 × 70.4 mm |
| Compression ratio | 8.5:1 |
| Fuel delivery | Mechanical fuel injection |
| Cooling | Air-cooled, engine-driven fan |
| Lubrication | Dry sump, pressure-fed |
| Oil cooling | Engine-mounted cooler plus front cooling coil |
Engine output
Horsepower, torque and engine speed.
Power is given on the booklet’s DIN basis. The 190 metric horsepower figure is approximately 187 mechanical horsepower; the separate period SAE rating uses a different test basis.
Factory booklet · printed pages 12–13| Peak power, DIN | 190 PS / 140 kW |
|---|---|
| Power peak | 6,500 rpm |
| Peak torque | 216 NmApproximately 159 lb-ft.22 mkp in the original table. |
| Torque peak | 5,200 rpm |
| Maximum engine speed | 7,300 rpm |
| Governed engine speed | 7,300 ± 100 rpm |
Performance
Top speed and acceleration.
Porsche specifies DIN empty weight plus half payload for the acceleration and standing-kilometre figures. For contemporary magazine results, explore the road-test archive.
Factory booklet · printed page 105| Maximum speed, manual | 143 mphApproximately 230 km/h. |
|---|---|
| 0–100 km/h (0–62 mph) | 7.0 seconds |
| Standing kilometre | 27.5 seconds |
| Nominal fuel consumption | 9.5 L/100 km |
Dimensions and weights
Dimensions and curb weight.
Dimensions are listed at DIN empty weight. The track measurements use the factory ride-height reference positions: front wheel centre 108 mm above the torsion-bar centre; rear wheel centre 12 mm below the transverse-tube centre.
Factory booklet · printed pages 102–103| Length | 4,147 mmApproximately 163.3 in. |
|---|---|
| Width | 1,610 mmApproximately 63.4 in. |
| Height, empty | 1,320 mmApproximately 52.0 in. |
| Wheelbase | 2,271 mmApproximately 89.4 in. |
| Front track | 1,372 mmApproximately 54.0 in. |
| Rear track | 1,354 mmApproximately 53.3 in. |
| Ground clearance | 150 mmApproximately 5.9 in. |
| Empty weight, DIN | 1,075 kgApproximately 2,370 lb.Manual-transmission specification. |
| Permissible total weight | 1,400 kgApproximately 3,086 lb. |
Wheels and tires
Original factory Fuchs wheels and tires.
The 1973 Porsche 911 S came standard with forged-aluminum Fuchs wheels in 6 J × 15 size, paired with 185/70 VR 15 tires. That is the factory specification for both front and rear wheels.
Fuchs wheels were developed for the first 911 S. Their one-piece forged construction combined low weight with strength; the five-spoke cloverleaf design became a signature of the early 911.
In 6 J × 15, the 6 is the rim width in inches, 15 is the rim diameter in inches, and J identifies the rim-flange profile.
Factory booklet · printed page 93Porsche · the Fuchs wheel story
| Factory wheel manufacturer | Fuchs (Otto Fuchs) |
|---|---|
| Standard wheels, front and rear | 6 J × 156-inch width × 15-inch diameter. |
| Construction | Forged light alloy |
| Standard tires | 185/70 VR 15Factory front and rear tire specification. |
Electrical system
Spark and sequence.
The factory table records these electrical details, including the firing sequence of the six-cylinder engine.
Factory booklet · printed pages 20–21| System voltage | 12 V |
|---|---|
| Battery capacity | 2 × 36 Ah |
| Alternator output | 770 W |
| Ignition | Capacitive discharge |
| Firing order | 1–6–2–4–3–5 |
1973 model
Oil capacity and fluid quantities.
The 1973 oil tank sits in the right rear wheel housing. The booklet lists total-system levels separately from the oil-change quantity; they describe different amounts.
Factory booklet · printed pages 104–105| Fuel tank | 85 litresApproximately 22.5 US gallons, including a 9-litre reserve. |
|---|---|
| Oil system, dipstick minimum / maximum | 11 / 13 litresApproximately 11.6 / 13.7 US quarts total-system levels. 1973 S with manual transmission. |
| Oil-change quantity | Approximately 10 litres10.6 US quarts per oil change. |
| Transmission oil | Approximately 3 litres3.2 US quarts. |
| Windshield-washer reservoir | Approximately 2 litres2.1 US quarts. |
UNDERSTANDING THE CAR
How the systems work.
Why does a small engine need so much oil?
The oil has two main jobs: lubricating the moving parts and carrying heat away. The 911 S may have only 2.4 litres of engine displacement, but its oil supply serves a separate tank, the engine, connecting lines and oil coolers.
Air-cooled, with help from oil.
The engine-driven fan blows air over the cooling fins on the cylinders and heads. Inside, circulating oil picks up heat from hot components, including bearings and pistons. The oil carries that heat to the coolers, where it passes through metal surfaces into the surrounding air. The factory S system includes an engine-mounted oil cooler and an additional front cooling coil.
The heat’s journey: engine parts → oil → cooler → air. The oil transports heat; the airflow carries it away from the car.
A reservoir for the road.
In this dry-sump system, most of the oil supply lives in a separate tank. A pressure pump feeds the engine, while a scavenge pump collects oil from the crankcase and returns it to the tank. This arrangement helps maintain a dependable oil supply during cornering and braking.
The generous oil volume also provides a thermal buffer: more oil takes more heat to raise its temperature by the same amount. That helps smooth temperature changes, while the coolers and airflow keep shedding heat during sustained driving.
Porsche Classic · how engine oil lubricates and cools
Factory booklet · lubrication and cooling
MECHANICAL NOTES
More mechanical questions.
How does the cabin heater work without engine coolant?
Fresh air passes around hot exhaust pipes inside the heat-exchanger housings. The warmed air supplies the cabin; the exhaust gases remain inside their own pipes. This is why the condition of the exhaust and heat exchangers matters to both heating and maintenance.
See the heat exchangers on this carWhat makes a forged Fuchs wheel different?
A forged wheel is formed by working metal under pressure rather than pouring it into a mold. Porsche’s original Fuchs design used a one-piece forged construction to combine strength with low weight. The familiar five-spoke outline is only one part of its design.
Factory sizes and Porsche’s wheel historyWhat does a valve adjustment accomplish?
The clearance in the valve mechanism allows for changes as the engine heats up. Adjustment sets that clearance to the specified value. Valve clearance, ignition timing and fuel-injection settings each contribute to smooth running.
Valve and ignition work on this carOn this car.
The figures above are Porsche’s factory specifications. The service history records what has been renewed on this particular car.
Fluid service · Entry 13