Mexacali Express ('72 K10/LQ4/TH350 Retrofit)

[jpstaub]

Even with Delphi's catalog linked in a post above there are a lot of choices to make. Some guidance follows:

1. GT series connectors are the easiest to work with when it comes time to take them apart. Say you put a terminal in the wrong position. With GT series connectors you can generally get the terminal out without much in the way of terminal removal tools other than a jeweler's screwdriver (not that this should solidify a decision since removal tools are pretty cheap). This is due to the tangless design of the terminals for this series.

2. Metri-Pack series connectors are harder to take apart. However, they are the choice for high amperage circuits. They take a terminal removal tool that's relatively common. The terminals are in the auto parts store supply chain. So, if you don't order enough terminals chances are fair that you'll be able to get more terminals without having to wait for a shipment. The same probably can't be said for GT series stuff.

3. Both style terminals require a crimping tool. Item #533 at Waytek is the lowest cost way to go. I've gotten good service out of my tool although if I were doing a lot of harnesses I'd upgrade.

4. Item #422 at Watyek will give you the ability to remove Metri-Pack terminals. I've also used it to work on Series 56 terminals. This one is well worth the money even if you don't play with wiring much. The first time you use it it'll pay for itself.

As far as connectors go relative to the retrofit wiring diagram in a previous post:

Connector A - This one mounts under the dash out of the weather so a sealed connector isn't necessary. Something in a 150 series will do the trick. Up to you how many cavities (the number of connections) you'd like. I used a six cavity connector for the ability to add an ECU generated vehicle speed signal and RPM signal at a future date. Four cavity is fine if you will never take that option.

Connectors B&C - These need to be weather sealed since they're located under the truck. 150 series 2 cavity is enough to get the job done.

Connector D - You can get away with a 2 cavity Metri-Pack 280 series that has a max continuous 30A rating. I've been using a 2 cavity Metri-Pack 480 series which has a max continuous 42A rating for added security. Just make sure the connector is weather sealed since it'll be in the engine compartment.

Connector E - A 150 series 2 cavity unsealed. You can use something even lighter weight if you'd like since both connections are moving small currents.

Connector F - A 150 series 3 cavity unsealed. Again, substituting something lighter would be fine based on the very small currents involved.

Finally, a quick note about ordering connector components. Always order more terminals than you'll need. I go about 20% more to cover my errors as well as errors on the part of the supplier. It sucks to be near the end on a wiring job and run out of supplies. Chances are you'll run out of the item that's impossible to find on the local market. By the way, unless you're lucky, buying anything connector related on the local market costs 5 to 10 times what it does when ordered from Mouser, Digi-Key, Watek, etc.