Spark plug leads

[Jodstar]

Just a question about spark plug leads. I have modern silicone leads with carbon core on the FC. I have noticed they are very common most other early cars as most original leads have since long been replaced. I was wondering if the "modern leads can affect the coponents" such as points,condenser & coil in any way. I have heard that modern leads can suppress the current and have a different affect on the system. I am more than happy to have original leads made up, as the FC is stock. Any ideas?
                                                   Cheers Jody

[craiga]

Jody,

The spark plug leads form part of the ignitions secondary circuit and are therefore electrically isolated from the primary side (points/condensor).  Changing from the original solid copper core spark plugs leads to the later carbon filled type will not effect these components. The original solid core cables contained almost no resistance and therefore full secondary voltage/current was available to the plug. This extra 'grunt' caused many tracking issues as the excessive and unused energy looked for an easier way to travel to ground. Misfiring was commonly a result, so was interference through any radio within cooeee of the car!

Unless you are absolutely fixed on originality I would use the later leads. You can buy the black bosch type which don't look out of place but will give better performance and  electrical noise suppression.

Cheers,

Craig.

[Jodstar]

Thanks for your time Craig,
                                            Jody