[johnny485]

In answer to your question re above.

The silvia and other cars wiring looms are designed to handle a certain amount of current at the nominal voltage of 12 Volts. If you fit higher power lamps either internally or externally and try to run them off of the existing loom, the lamps will be drawing more current through the loom to satisfy their need. This will in turn lead to a situation where the loom will heat up. Now, as the the wiring looms in the S12's are pretty old, there will be ageing of the conductors leading to an increase in their resistance, this is inescapable, the net result no matter which way you slice it is; A heating effect with either excessive or higher current drawn.

If you really do want more powerful lamps and want to use them in the original position then as a matter of safety, I would make a replacement loom, connectors and all, and use a relay fed from the battery which would be switched from the original light stalk or control relay.

This of course seems rather a lot of work but, considering I do not know exactly the headroom designed into the loom and taking into account the ageing effects of it this, I'm afraid to say, is the best I can offer at this time.

kind regards,

john