I have owned since new a 1971 2.2 ltr 911T with two batteries, one behind each headlight. How do I trickle charge them while leaving them in the car? Can I use a ctek style and plug it into the cigarette lighter on the dash? I have used the ctek charger in my 2006 Carrera S with no problems, but am not sure if the electrical system in the old car can handle it. Any help or suggestions would be appreciated.

 

Just hook the charger to one of the batteries.

I always stored my early (two battery) cars with the negative disconnected on each battery which requires that both batteries be charged separately. Why? They discharge quickly and are expensive to replace.

 

Don't backfeed any charger on the old cars through the cigarette lighter.