IGN-1A Ignition Coils

IGN-1A Ignition Coils



Haltech Part Number HT-020114

The IGN-1A coil is a high output inductive coil with an internal igniter module.  Exceptionally high power levels can be achieved using this ignition coil, all the while retaining the benefits of longer spark duration found with conventional ignition coils.

Why Is a Long Spark Duration Beneficial

Under low air flow conditions, such as idle or light throttle, there is very little air making it into the cylinder. Under these condition very little fuel is being delivered as well.   For combustion to take place an amount of air and fuel at the correct ratio needs to be present and for the spark to actually hit it.  If the fuel being delivered is not atomised very well, as often found with high flowing injectors, the air and fuel will not mix together very well. If so there is a chance that the spark may not actually ignite any fuel, and a misfire occurs.  This often is the case when a CDI system which has an intense but very short duration spark.  Normally to work around this issue more fuel is added (richer) so there is a greater chance the spark will hit the fuel.  Sometimes the ignition timing will be retarded to give more time to squish the air and fuel together to also increase chances of the spark hitting the mixture.

The other solution is to use an ignition system with a longer spark duration.  This gives more time for the spark to actually hit some of the air and fuel mix, ensuring combustion takes place.  This is why almost all OEM ignition systems use an inductive rather than a capacitive ignition system. With the IGN-1A ignition coil being of an inductive type it offers a long duration spark which provides good resistance to light load misfire.



Haltech Elite Series Setting
Ignition Mode
Installation Dependent
Ignition Edge
Ignition Dwell Mode
Constant Charge


The IGN-1A is unique in that it is thermally limited in how long the coil can be charged.   Full coil saturation does not occur until a high dwell time, however maintaining the coil at full capacity can cause it to become hot.  As such the dwell time needs to be left lower than normal to maintain reliability, and only under high power demands should be dwell to configured to give full spark energy.  To achieve this the dwell table can be mapped over battery voltage and also engine load.  

Below is an example of how this can be achieved.

At a normal running 14V the coil is charged at 4.5ms under conditions off boost.  As boost pressure rises the dwell will gradually increase until it peaks around 200kPa (~30psi) where full spark energy is then available.  This allows excellent spark energy together with good reliability.

Also at lower voltages such as when the engine is cranking the dwell time is also lifted to ensure a strong spark to aid engine starting.



12V Power Supply

The IGN-1A coil can draw up to 15A.  If high rpm and high power is being used, together with conventional 30A Relays to provide power, it may be necessary to have a separate fuse and relay for every pair of coils.  This has been seen on some rotary installations where over 10,000 rpm is used together with high boost.

If the wiring is also not cable of supplying the current required it can also limit the spark output.


The number of grounds (3x) on this coil often cause confusion.  If in doubt, all grounds can be joined together and run the to cylinder head.  This can eliminate issues if there is a poor engine ground strap that then pushes high current through the coil.  It can also prevent a coil from firing if the engine grounding is not sufficient, and this happens as the ground lifts on the ECU signal preventing triggering. The fix is of course to improve the engine grounding. 

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