Lucas 70 amp alternator

I bought the “uprated” 11AC style 70 amp Lucas alternator from SNG. It has only three connections, AL, B+ then one labelled D+ (or possibly O+). Not the same as the original which has four, AL, B+, F+ and F-. Anyone know the wiring for this? It’s way above my pay grade.

John North
S1 Roadster

Yes. It’s an internally regulated alternator, not an 11AC. However, very easily hooked up. The B+ serves the same function as the B+ on the Lucas. The only problem being that it’s a 70 amp alternator, and exceeds the capacity of the wiring. But easily fixed by running an extra 10ga wire between B+ and the + junction post behind the battery. This is in addition to the stock B+ wiring.

As for the rest, you need to locate the 3AW under the heater box. Unplug the AL and WL wires and connect them together. Then at the alternator, plug the AL wire into the D+ terminal. You will need a good light bulb in the dash and it cannot be an LED. (If you don’t want the dash light, you can plug your F+ wire into D+ and tape off the AL.)

The F+ and F- wires can be taped off. The voltage regulator and alternator relay aren’t needed, but you can leave them in place for appearance.

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Thanks for the detailed help!