Electronic Ignition FAQs
The following is a list of questions we have been asked in the past. If your answer is not here please contact us.
- What is the difference between Standard and Ballast ignition systems?
- How can I tell if I have a standard or ballast system?
- How can I tell if I have the correct coil?
- I want to fit a AccuSpark. Does it matter if I have a standard or ballast coil?
- Can I change from a ballast to standard coil?
- Why do I need to set a points gap is the AccuSpark any better?
- What is Dwell?
- What happens if my AccuSpark fails.
A Standard 12 Volt ignition has a standard ignition coil that produces a full power spark at 12 volts. A Ballast ignition has a ballast coil that produces a full power spark at a reduced voltage , the voltage is dropped by placing a ballast resistor or a resistor wire in the live feed to the coil. The coil will have a second feed running from the starter solenoid ,this will supply a full 12 volts on cranking giving the coil 125% the voltage it needs enabling a stronger spark at start up. Once the car is running the 2nd feed is cut and the coil will be powered by a reduced voltage.
Most British cars had a standard ignition up to early 1970s when replaced with the ballast system. A standard system will only have 1 wire on the + side of coil.(Not including any suppresser wires) A Ballast system will have 2 feeds on to the + side of coil.(Not including any suppresser wires)
If the coil does not have standard or ballast written on the front you will need to test with a multimeter. Set meter to Ohms. test between + and -. A standard coil will read around 3 Ohms a Ballast coil will read around 1.5 Ohms.
The AccuSpark will work with both Standard or Ballast coils. But requires a Ohms resistance of not less than 1.4 Ohms. If the resistance falls below this it will cause the unit to run hot and reduce overall life.
To replace a Ballast coil with a standard coil is quite simple. If you have a visible resistor you just need to bypass and connect the live feed direct to the coil. If you have a ballast wire this may be more difficult to identify. This may be a wire from the ignition key to coil or may just be a part of the wire. Normally the ballast wire will have a unique colour in the loom to make it easier to identify. If you are unsure just run a full wire from the Ignition key to the + side of the coil.
The coil needs to charge between each spark ,it does this while the points are closed and creating a circuit.As the distributor turns it opens and closes the points. If we set the points gap to big the points will only be closed for a short time and may not be long enough for the coil to charge. If we set the points gap to small the points will be closed for to long and the coil will become saturated. The AccuSpark completely does away with points and condenser. It has no moving parts once fitted it will require no maintenance of any kind.
The Dwell or Dwell Angle is the degrees of rotation that the points are closed divided by the number of cylinders. i.e. a 4 cylinder car will have 90 degrees of rotation for each cylinder if the points are open half the time the dwell would be 45 degrees. When points are fitted this requires regular checking for correct running.The AccuSpark completely does away with points and condenser and fully handles dwell time.
If you are unfortunate to have a failure. As the unit requires no modification to wiring or distributor the points can be retro fitted at any time. The AccuSpark comes with a 3 year warranty. Please click here to see our returns procedure.