The Classic Parts resistor is a one Ohm 50 Watt resistor. It's labeled, if you just zoom the photo a little. That's way too small. The 1 Ohm is fine- - - -(maybe)- - - -but the resistor needs to be rated for about 200 Watts or so to keep it from overheating. To figure how much voltage the resistor drops, it's necessary to MEASURE (not guess about) the current flow of the end item such as a blower motor, etc., with it operating with the resistor installed. The idea is to dissipate HALF the applied voltage with the resistor, and the other half with the motor, etc.

Example:

Engine running, battery terminal voltage is 14.5 Volts. The resistor needs to drop 7.25 Volts, and the accessory needs to run on the other half.

If the item draws 10 amps at 7.5 volts- - - -it's using 75 watts of power. The resistor will also be producing 75 watts of heat. There is NO substitute for measuring current draw AFTER the dropping resistor is installed, and tinkering with the resistance value until the accessory sees the voltage it needs.

THERE ARE NO SHORTCUTS!
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!