New ignition trouble, MAYBE

Factory style regulator?

Is it the flat one for the 70 up cars, or the cube one for 69 down?

If it charges at a steady 15 volts(doesn't go up to 17 or something if you rev it up) then it probably has a voltage drop to the ignition lead on the regulator. It then thinks the system voltage is lower than it really is, so it boosts the output to push it up.

Check the voltage opn the ignition lead(at the reg) with it running. You will probaly find it is 1 to 1.5 volts lower than at the battery direct.

If this is the case there's 2 ways to fix it.

1)spend 2 days looking for the drop, and another week rewiring the ignition switch circuit when you find it. Make sure you colour code it all correctly.... :shock: :pale:

2) use the existing igntion lead on the reg, to turn on relay with direct battery voltage to the reg.
It works well and is a 15 minute fix.

The reason I ask about the type of reg is that the old style one can be used, by grounding the second terminal on the alternator.

If you are using the newer style, just stick with it. The stock replacement is just as good as any of the aftermarket stuff.