View Full Version : Alternator upgrade and stock wire harness

07-25-2006, 11:58 PM
I have an alternator to add to my 56 Tr3 and was wondering if anyone has had any problem with the stock harness and more potential ammperage? (Presently everything on my stock harness works correctly and seems in good repair). Headlights for example, upgraded to halogen, will draw more juice and can the original wiring safely handle the load? I know many have changed to alternators so what theory and experiece do we have?

07-26-2006, 11:40 AM
The Lucas generator wiring was probably sized for no more than 20-22 Amps. On later cars that I'm more familiar with the common way of addressing this during an alternator conversion is to run an additional wire from the output of the alternator directly to the hot terminal on the starter solenoid. This is an additional wire, it doesn't replace the one in your existing harness. The additional wire is normally 10 AWG wire but larger won't hurt if you care to use it.