Rotor Arms / Point Sets
Fits:
Porsche 924 Turbo 1981>>
The "rotor" head is attached to the top of the distributor shaft which is driven by a gear on the engine's camshaft and thus synchronized to it. This rotor is pressed against a carbon brush on the centre terminal of the distributor cap which connects to the ignition coil either through the top and wired directly to the coil in HEI systems, or via the centre terminal in points ignition systems and remotely connected to the coil.
The rotor is constructed such that the centre tab is electrically connected to its outer edge so that voltage coming in to the centre post travels through the carbon point to the outer edge of the rotor. As the camshaft rotates, the rotor spins and its outer edge passes each of the internal plug terminals to fire each spark plug.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93160290600
The product you are viewing cross references to these numbers
- Porsche 924 Turbo 2.0L 1979-81
- Porsche 924 Turbo 2.0L 1982-84
Shop Securely
12 Month Warranty
Worldwide Delivery
Fits:
Porsche 924 Turbo 1981>>
The "rotor" head is attached to the top of the distributor shaft which is driven by a gear on the engine's camshaft and thus synchronized to it. This rotor is pressed against a carbon brush on the centre terminal of the distributor cap which connects to the ignition coil either through the top and wired directly to the coil in HEI systems, or via the centre terminal in points ignition systems and remotely connected to the coil.
The rotor is constructed such that the centre tab is electrically connected to its outer edge so that voltage coming in to the centre post travels through the carbon point to the outer edge of the rotor. As the camshaft rotates, the rotor spins and its outer edge passes each of the internal plug terminals to fire each spark plug.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93160290600
The product you are viewing cross references to these numbers
- Porsche 924 Turbo 2.0L 1979-81
- Porsche 924 Turbo 2.0L 1982-84
Shop Securely
12 Month Warranty
Worldwide Delivery
Fits:
Porsche 924 Turbo 1981>>
The "rotor" head is attached to the top of the distributor shaft which is driven by a gear on the engine's camshaft and thus synchronized to it. This rotor is pressed against a carbon brush on the centre terminal of the distributor cap which connects to the ignition coil either through the top and wired directly to the coil in HEI systems, or via the centre terminal in points ignition systems and remotely connected to the coil.
The rotor is constructed such that the centre tab is electrically connected to its outer edge so that voltage coming in to the centre post travels through the carbon point to the outer edge of the rotor. As the camshaft rotates, the rotor spins and its outer edge passes each of the internal plug terminals to fire each spark plug.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
93160290600
The product you are viewing cross references to these numbers
- Porsche 924 Turbo 2.0L 1979-81
- Porsche 924 Turbo 2.0L 1982-84
Shop Securely
12 Month Warranty
Worldwide Delivery
Rotor Arms & Contact Points Sets – Precision Ignition Components for Classic Porsche Models
Rotor arms and contact point sets are essential parts of your Porsche’s ignition system, responsible for controlling spark distribution and timing in vehicles with mechanical ignition setups. Together, they ensure the correct firing sequence, providing reliable combustion, smooth acceleration, and efficient engine performance.
At Design911, we stock a complete range of genuine and high-quality rotor arms and contact point sets for classic and early Porsche models, including 911, 912, 914, 924, and 928. Each component is designed for precision fitment, long-lasting performance, and consistent electrical delivery — maintaining your Porsche’s originality and reliability.
What Do Rotor Arms and Contact Points Do?
In traditional distributor-based ignition systems, these
components work together to generate and distribute the spark required for
combustion:
- Rotor
Arms: Spin inside the distributor cap, transferring the ignition
coil’s high-voltage current to each spark plug terminal in turn.
- Contact
Points: Open and close the electrical circuit in sync with the
engine’s rotation, controlling coil discharge and ignition timing.
- Together: They maintain accurate spark timing for smooth running and efficient power delivery.
These components are crucial for keeping classic Porsche engines firing reliably and performing at their best.
Why Do Rotor Arms and Contact Points Fail?
Over time, heat, friction, and wear can affect the
performance of these ignition parts. Common causes of failure include:
- Contact
wear or pitting from electrical arcing.
- Carbon
buildup reducing spark efficiency.
- Rotor
arm erosion or cracking from high voltage or vibration.
- Mechanical
fatigue due to mileage and age.
- Corrosion or contamination in the distributor housing.
Symptoms of failure include hard starting, misfires, engine hesitation, or loss of power, particularly at high revs or under load.
Why Replace Worn Rotor Arms and Contact Points?
Replacing worn or damaged ignition components restores accurate spark timing and smooth engine performance. New, high-quality rotor arms and contact points improve combustion efficiency and prevent further ignition system wear.
Benefits of replacement include:
- Reliable starting and smoother idling.
- Improved power delivery and throttle response.
- Reduced misfires and fuel consumption.
- Long-term reliability with manufacturer-quality precision.
All components in our range are built using high-grade materials with precise machining and durable contact surfaces, ensuring consistent spark delivery and long-lasting performance in vintage and air-cooled Porsche engines.
