123 Ignition Question

[baldyz1]

Hi,

I know there are some threads around similar questions which I have read.

I have a series 1 1966 and the rev counter has been modified to generate directly from the coil. This is a single cable solution. The rev counter will have a seperate switched feed and earth as part of the standard loom (Red and Black).

I note that best advice suggests a separate wire from an ignition feed direct to the 123 distributor. My loom has a dual shrouded cable that runs to the coil and only one wire is currently utilised to provide a signal so I could use the 2nd for a direct feed to the 123. The cable thickness is average for the loom i.e. it is similar to most of the dial cables and not as thick as say the headlamp cables. Would this be sufficient or do I need a heavier cable and if so any advice on the guage would be appreciated.

The dash is mostly apart so running cables is no big deal but I wanted to use cables that are already part of the loom so it all looks original. I could of course buy some material cable wrapping if needed.

Many thanks
Chris

[bitsobrits]

Chris,

The operating current of the 123 unit is <100mA according to the 123 installation directions listed on their webpage, which means even an 18 gauge wire woulds be sufficient. I believe all of the small gauge wiring in the E loom is 16 gauge, so much heavier than required.

The 123+ distributor in my car is fed from the coil primary side, and has been happy to do so for the last several years. But if you have an additional wire to use, that is a good alternative.

[baldyz1]

Thats perfect information. It will keep the loom tidier, I hate adding extra wires if its not necessary plus using a wire that has the correct color code is less confusing for someone who revisits later.

Many thanks
Chris