I have a 76 f150 4x4 for off road use. It is old and in rough shape, but the drive train remain strong w/ the 300 big six. I have two KC lights plus the orig headlights and want to add two more 130 watt driving lights. However, i don't know if this will put too much strain on my battery or alternator or some other component. You input is apprec.

the battery is new, the alternator old but working. any advice on what to be careful w/ etc. is desired.

 

No one?

 

well i know that KC are very powerful lights
i have three sets of cheep walmart lights on mine, if i turn them all on i can watch the battery guage on the dash drop too much and they dim when the truck is idleing with only one set on
i imagin that will be too much for yours, a bigger alternator will help

 

I used to have 12 150W'ers on my 2000 F-150 w/ the factory battery & 130A alt. Of course that was a brand new truck though. A high amperage alternator would help out a bunch. Don't over look the size of the wire, this can cause some voltage drop & could be a fire waiting to happen. Make sure everything is fused & you are using relays to switch your power. Good luck.

 

There should be a chart on the net for what size alt and battery you need to handle alot of lights.You see rigs setup with hi power lights that a reg alt could not handle.But wait just put a power plant in the bed and run anything you want LOL.I ran air craft landing lights back in my younger days and that was a low end alt setup about 55 or 65 amp output.But the new lights they have out now make them look like reg lights for being bright.Fire and police vel's have too have hi output alt's for the elect they run.Well that's my 2 cents

 

Mattadams is the one to talk to. Although he runs PIAA's. Im sure he can give you an idea.

 

Peak alternator output is someplace above idle. At idle, if you're only getting 50% of the rated amperage, you're still talking at least 60A being put-out by the alternator.

Most of the older alternators would put out around 90 or so amps at peak output.

A set of 150-watt KC Daylighters will draw 13A each. For a set of 4, you're looking at 52A in addition to the existing power being used to run the engine and other accessories (lights, stereo, blower, etc.)

If you wire everything up to draw from the battery, the battery acts like a, well, battery. it'll help augment the alternator output for intermittent light use, but for continuous running, you may find you need more juice.

-Joe