Anytime you join two wires together, there is the risk of a poor electrical connection. This can manifest itself either as a bad connection where current and voltage is converted to heat, or the connection can be severed entirely. Many moons ago, GM created the slick WeatherPak connectors that use male and female pins positioned by large plastic holders with soft rubber seals designed to keep out moisture and dirt. These were originally intended for computer sensors where the voltage is usually less than 5 volts and a good connection is mandatory.
They worked so well that MSD has brought them to the market under the Weathertight name. While designed mainly for low-amperage connections using 16- to 18-gauge wiring, you can squeeze a slightly larger wiring. The only downside is that they require a specific tool to crimp the wire to the male and female pins, but with the tool, installation is easy. MSD does offer a professional crimping tool, but it's mighty expensive. Or if you already own MSD's Pro-Crimp spark plug wire crimping tool, MSD offers specific Weathertight jaws.
The major advantage to these connectors is that you can disconnect and reattach them hundreds of times without worrying about bad connections. They also make an audible snap when fully engaged and require significant effort to pull apart. Plus, MSD offers an extractor tool that makes changing the wires a breeze. The connectors are molded from a special nylon material that will withstand a temperature range of -40 to +275 degrees F and are indexed so they only attach one way.
Applications could be a quick-disconnect for your distributor, making your own harness in a build-it-yourself electronic fuel injection, wiring solenoids and relays for a mild nitrous system, ignition retard modules, or ignition rpm switches. It takes a little more time to create these connections, but once you're finished, they could easily last the life of your car-perhaps longer.
Parts List All these parts are from MSD, while prices were obtained from www.summitracing.com.
| Component | Part Number | Price |
| 6-pin Weathertight | 8170 | 12.70 |
| 4-pin Weathertight | 8171 | 10.00 |
| 3-pin Weathertight | 8172 | 8.00 |
| 2-pin Weathertight | 8173 | 8.00 |
| 1-pin Weathertight | 8174 | 7.00 |
| 12-pin Deutsch | 8186 | 25.00 |
| 8-pin Deutsch | 8185 | 17.00 |
| 6-pin Deutsch | 8180 | 14.00 |
| 4-pin Deutsch | 8181 | 9.00 |
| 2-pin Deutsch | 8183 | 6.00 |
| Pin-extraction tool | 8193 | 13.00 |
| Pro-Crimp tool | 3505 | 50.00 |
| Weathertight dies | 3509 | 28.00 |
| Deutsch dies | 3510 | 28.00 |
| Professional crimp tool | 8192 | 167.00 |