A breakerless ignition conversion is essential to enhance the performance and fuel consumption of your classic or vintage car.
Breaker point-type ignition systems rely on points to mechanically open and close the electrical circuit to the spark plug at a precise time.
Breakerless ignition systems replace the breaker points with electronic components to eliminate the mechanical contact switching.
These electronic triggering devices are more efficient and reliable, and here’s how to go about the conversion process.
Table of Contents
- What Is Breakerless Ignition Conversion?
- Why Replace Contact Points (Breakers) with a Breakerless Ignition System
- How a Breakerless Ignition System Works
- Wrap Up
What Is Breakerless Ignition Conversion?
Breakerless ignition conversion involves switching your vehicle’s ignition system from the breaker to the breakerless or electronic ignition system.
Breaker points operate via electrical current interruption, cutting power flow to the ignition coil primary winding.
When this camshaft-driven switch cuts the power flow, it collapses the magnetic field in the primary winding, inducing a high voltage in the secondary winding.
This high voltage appears on the coil’s output briefly and is enough to generate an arc across the spark plug gap.
A breaker-point ignition system
The rapid mechanical opening and closing causes high wear on the breakers and cam followers, including due to pitting (caused by electrical arcing).
You can solve the arcing issue by installing a capacitor parallel to the breaker points.
However, the most critical drawback of this mechanical system is inaccurate timing when revving the engine at high speeds.
Although you can adjust the dwell angle, the mass of the breaker increases at high speeds, resulting in inefficiencies.
So, the only way to solve the issue is to switch to an electric breakerless ignition.
A breaker arm with contact points
Why Replace Contact Points (Breakers) with a Breakerless Ignition System
It would be best to consider the electronic ignition conversion because you’ll experience these benefits.
Better Reliability
Breaker points have a high wear rate due to the moving parts and can result in misfires or inaccurate ignition timing.
But breaker systems experience minimal wear, making them more reliable.
Enhanced Engine Performance
Less wear means breakerless ignition systems deliver hotter ignition sparks consistently with precise timing, which makes the engine run smoothly.
Better Fuel Economy
Precise ignition timing with zero or minimal misfires improves the vehicle’s fuel economy while reducing emissions.
An electronic ignition control module
Lower Maintenance/Maintenance-free Modules
Breakerless ignition systems last longer than breaker points because they don’t have physical contact points.
And they require minimal maintenance throughout their operational lifespan.
Easier Timing Adjustment
These systems usually don’t need any timing adjustment because the triggering devices don’t wear out.
And even if they require adjustments, the process is more straightforward and enables precise tuning.
Quick Starting
Breakerless ignition systems deliver a higher ignition voltage that creates hotter sparks consistently via the spark plugs, enabling faster starting, especially during cold weather.
How a Breakerless Ignition System Works
This electronic ignition technology must know the exact piston position in the engine to determine the precise time to generate a spark.
The piston position data usually comes from the camshaft or crankshaft, which activates an electronic trigger to produce the spark.
Breakerless Ignition Triggering/Timing Systems
Newer vehicles have these triggering sensors installed on the engine block for rotation by the crankshaft.
But in old vehicles with distributors, these timing sensors operate based on the distributor shaft’s rotation from the camshaft. These triggering systems include the following.
A schematic of an electronic ignition system
Hall Effect Sensor
A Hall effect rotary-vane sensor is a thin semiconductor wafer material that has a voltage applied to it constantly.
It also features a magnet mounted on the opposite side of the sensor with an air gap between the two.
The magnet creates a magnetic field that acts on the semiconductor sensor constantly unless an interruption occurs between them.
This metal tab that causes the interruptions does not touch or make contact like when using breakers. It only has to block the magnetic field.
A Hall effect magnetic encoder
The interruption or blocking lowers the output voltage from the sensor, signaling the ignition control module to turn off the transistor, which cuts power to the ignition coil.
This primary winding current interruption makes the coil fire, sending a high ignition voltage to the connected spark plug wire.
Therefore, this switch or sensor can detect the position of the toothed cam or wheel inside the distributor as it spins due to the output voltage drop from the sensor.
The ignition control unit does a more precise job of determining the exact timing to generate the spark.
Depending on the vehicle generation, this trigger can sit on the crankshaft or camshaft-driven distributor.
Magnetic Pickup
This pickup sensor features a stationary magnetic pickup coil spaced from a ferrous, toothed rotor called a trigger wheel or reluctor.
When one tooth on the rotor aligns with the stationary pickup coil, a tiny alternating current gets generated in the coil wire, creating an analog signal coil output to trigger the ignition control module.
After receiving this signal, the module switches off the power transistor, interrupting power flow to the ignition coil primary winding. This action causes it to fire.
A distributor cap with spark plug wires attached to it
The system has an air gap between the pickup coil and the reluctor that eliminates physical contact.
This reluctor is connected to the camshaft-driven distributor, with the pickup coil inside the distributor to sense the rotations.
In newer cars with distributorless ignition systems, the trigger wheel sits on the crankshaft or flywheel with the pickup coil on the engine block or front cover.
Optical Sensor
Optical systems differ from the two triggers above because they rely on light. They feature a rotor plate, a photosensitive diode receptor, and an LED.
The rotor plate is responsible for timing because it features multiple slits to allow the light through from the LED to the receptor.
An optical sensor
So, as the rotor plate spins when rotated by the camshaft, it interrupts the light beam hitting the optical sensor.
When this photosensitive diode does not receive light, it sends a voltage signal to the ignition control module, informing it to fire the ignition coil to generate a spark.
Wrap Up
Breakerless ignition conversion involves switching the breaker point ignition system with either of the three electrical trigger ignition switch mechanisms above inside the breaker point type distributor.
This distributor modification requires a skilled electrician or mechanic to avoid costly engine damage.
Therefore, if you are not an expert, we don’t recommend trying this electronic distributor conversion as a DIY project.
That’s it for now. We hope the article has been insightful. Comment below to leave your feedback.
