* Correct Length: Measure the distance from each spark plug to the distributor cap. Get wires that are the appropriate length for your engine's configuration. Too short and they'll be strained; too long and they'll flop around, potentially causing misfires or damage. Many suppliers offer pre-made sets for AMC 304s, making this easier.
* Correct Material: Choose a high-quality wire. Silicone core wires are generally preferred for their resistance to heat and cracking. They often outperform standard rubber-core wires, especially under the hood of a vehicle.
* Correct Terminals: Ensure the wires have terminals that fit both your spark plugs and your HEI distributor cap. HEI caps typically use a specific terminal type. Double-check compatibility.
* Suppression: HEI distributors generally have built-in suppression. However, it's good practice to use wires with good suppression properties (they'll be advertised as such) to minimize radio frequency interference (RFI) which can cause issues with your radio or other electronics.
Don't just buy "universal" plug wires. While they might seem cheaper, it's usually better to get a set specifically designed for a 1970s-1980s AMC 304 to ensure proper fit and length. Otherwise, you risk improper routing, potential damage, and poor performance.
To find the right wires:
1. Identify your distributor: Knowing the exact make and model of your HEI distributor helps narrow down the choices.
2. Measure your existing wires: This gives you a good baseline to compare.
3. Search online retailers: Search for "AMC 304 HEI spark plug wires" or use the distributor's make and model in your search. Many reputable parts suppliers offer pre-made kits specifically for this application.
4. Check with a local auto parts store: They might have a selection of wires, or be able to order them for you.
By taking these precautions, you'll ensure a proper and efficient ignition system for your AMC 304 with your upgraded HEI distributor.
