We love creature comforts. Though we openly lament the complexity of our daily drivers we think nothing of heaping electrical devices on our fun cars. We'll go way out of our way to get power windows, power door locks, high-watt audio gear, climate control, high-powered lights, and electronic engine management.
Unfortunately, the effort we invest in electrical devices doesn't seem to extend to their installation. Generally speaking we mount electrical components well but we tend to drop the ball when it comes to integrating them with the rest of the electrical system. Most of us simply hard wire a device to the rest of the system and dread servicing the part or any other one near it. Because to remove a hard-wired electrical component means cutting its wires and that means having to reconnect wires likely made too short by the splicing junction. Creating joints with spades and push-on terminals seems like a good idea but a bunch of nearly identical-looking wires each equipped with the same type of terminal is a nightmare puzzle when working upside down and backward under a dark dash. That's no way to live.
Fortunately, it's not the only way to live either. As early as the '50s auto manufacturers began equipping electrical components with multi-terminal connectors or plugs. Need to service a device or get to one behind it? Just pull the plug and remove the part. And because of the plug's index only one-way reconnection happens just as effortlessly.
And that's really only the start. Because the OEMs used these multi-terminal connectors for decades they're considered service items. They're available just about everywhere and as a result they cost peanuts—new ones from the right sources cost so little that it's not even worth harvesting used pieces.
What follows is what you need to know about the three most popular connector styles: Packard 56, Weather Pack, and Metri Pack. There are others but since they lack the utility of these three we'll save them for another entry.
For now, though, learn what it takes to make a wiring installation as serviceable as the one in your new car. These connectors are so handy, affordable, and easy to use that you'll wonder how on earth you did without them so long.
The Packard 56 is the grandfather of the modular electrical connector. If the Packard name sounds familiar it's for good reason: the Packard brothers of automobile fame started it in 1890. In fact the Packard Electric Company bankrolled the Packard Motor Car Company nine years later.
In 1932 the brothers sold Packard Electric Company to General Motors who named it the Packard Electric Division. The company released its 56 series as an un-sealed modular system in the mid '50s. The housings come in a variety of configurations, from plain inline connectors to specialty connectors that correspond to various devices, like sending units, flasher modules, ignition switches, alternator plugs, and, certainly most familiar, three-pin headlight plugs.
The Packard 56 terminals fold over the conductor to form a high-pressure crimp that seals the conductor strands as a soldered joint does yet achieves a superior electrical connection than solder can. The terminals also alleviate strain on the exposed conductor with a secondary crimp that grabs the wire jacket. All 56-series connectors use 1/4-inch blade-type terminals that can handle as much as 48 amps continuously. Though the terminals require a special crimp tool, popularity has made powerful ratcheting models refreshingly inexpensive.
Packard 56 connectors are small and unobtrusive. Since they date to the '50s they're historically possible on a period hot rod or custom (though unlikely at the time since the tools were once exceedingly expensive). The lack of sealing means they don't work well in damp locations, so keep them close to the engine compartment or interior. And they can be a real bear to connect and pull apart, especially when cold or in tight confines.