Actually Getting Started: The Ignition System:

     I am not a great expert in this field so I will make it short and simple as I couldn't honestly go into any more detail and claim to know what I was talking about.

Parts Prices:

- New Aldon performance tuned distributor £110
- Electronic ignition module £60>250
- Good quality silicone cored plug leads £20 a set
- Three dimensional computer ignition system £350>1000

Contact Breaker Ignition:

     This is what you have now (if you haven't already fitted Electronic ignition).
When in perfect condition it can produce almost as much power as an electronic system, however it is rarely in such condition and so for consistent trouble free performance fit an electronic system.

The Distributor:

     The standard Lucas one is fine but will probably require different bob weights to alter the timing in a tuned engine. Alternative weights are available at very modest cost from Triumph Tune.

     Weber DCOEs and also I believe most if not all Weber DGV do not require a vacuum line to be fitted. Different distributor weights will be needed to compensate though. Do not attempt to alter a carb or manifold to accept a vacuum line where one is not required.

AC Delco distributors as fitted to earlier Spitfires are generally regarded as inferior in build quality to the Lucas unit. Unfortunately I am not aware of any alternative units to the Delco one although I have heard of US Mallory units being attached to Spitfires. Mallory are certainly superb but I don't know if they can be fitted to early or just late models of Spitfire.

     Aldon Ignition in the UK do new performance tuned Lucas style replacements, I am unsure if they do one to fit the old Delco equipped engines.

Electronic System:

     This works by using either magnets or optics to trigger the spark and is more accurate and can use higher voltage coils as the points wont burn up. The high voltage coil means you can open the plug gap up a little to burn the fuel slightly more effectively, not much more though. Starting will improve too especially on cold damp mornings.

Cons and Garbage Info:

-      Be very careful about magic electronic gizmos that increase power by 20%. They are lying, a system called (unfortunately) a Spitfire often marketed at shows has been tested to show no measurable power gain. Many `wonderful` plug leads claim similar sort of daft power gains and I don't believe a word of it. Fit some quality cheap silicone cored leads and forget.
-      There ARE many very expensive and cunning systems that can provide more power through better ignition but these are usually race car only (due to expense) and certainly don't give 20% more power!
-      Those marvellous looking 4 pronged spark plugs do not increase power, they just last much longer as the spark moves onto the next prong once one has been burnt and sooted up.

Useful info:

      When an engine has been modified consider fitting spark plugs with a different heat range, the rolling road will know which ones to try so bear in mind your new powerful engine may run better on different than standard plugs. Spark plugs are designed to burn off the combustion deposits at certain operating temperatures, when you alter them by tuning an engine the plugs MAY need to be changed to continue to burn off deposits and avoid sooting up.

3D Mapped Ignition Modules:

     These systems alter the ignition timing based upon engine speed, throttle position and Rpm.

     They can be fitted to any engine with a Weber DCOE carb as the throttle sensor bolts to it.
Most can be mapped at home on a PC and come with all kit from £350. They do provide a power advantage and more economy but again you are not talking about 20% or even 10% more power.