I have been trying to drop the voltage for the fans and wiper in my 54 dodge. I have tried the two that speedway sells, the first was the finned metal job with a pin on either end, and the second was the ceramic and metal one with a resistor built in.

As soon as I hook one up I get nothing from the engines. They will not move on hi or low settings.

These are stock fans and 2 speed wiper, and stock switches. Anyone have any luck dropping these or do I even have to? They run with 12 and do not seem overly fast on it either. Hell I didn't even reverse any wires on the wiper, as it has three coming out so there is no good way to do it.