Champion 25-1 Spark Plug

Champion 25-1 Copper Plus Spark Plug

Champion Copper Plus 25-1 is a replacement spark plug built for dependable ignition performance in a wide range of classic cars, trucks, and vans. It uses a copper core electrode for improved conductivity and heat control, helping maintain consistent operation in older engines that rely on stable secondary ignition.

Key Features

• Copper core electrode for strong conductivity and heat management
• Nickel center electrode tip and nickel ground electrode core material
• Pre-gapped at 0.035 in. / 0.90 mm
• Resistor type plug for ignition system compatibility
• Tapered seat design with 14 mm thread diameter and 0.441 in. reach
• Removable nut terminal and 0.625 in. hex size
• Champion Copper Plus Small Engine classification

Product Details

The Champion 25-1 spark plug is part of the Copper Plus line, a product family focused on practical ignition service for everyday repair and maintenance. Its copper core construction supports conductivity and heat transfer, while the nickel electrode materials are selected for steady wear characteristics. The RV17YC plug type, 17 heat range, and tapered seat design make it a direct-service option for many older domestic applications, including Chevrolet Caprice, Ford Mustang, and Dodge truck platforms listed in the fitment data. This part cross-references Autolite 26 and Autolite 147 for the same application.

What It Helps Address

• Hard starting caused by worn or inconsistent spark plugs
• Misfire conditions from degraded secondary ignition performance
• Rough idle in older carbureted or distributor-equipped engines
• Heat-related plug wear in high-mileage engines
• Service issues on classic Chevrolet, Ford, Dodge, GMC, Pontiac, Buick, and Oldsmobile applications

Installation Notes and Tips

Verify the plug type, thread diameter, reach, seat style, and heat range before installation. The pre-gap is set to 0.035 in. / 0.90 mm, but final gap should always be checked against the vehicle service specification. Confirm the removable nut terminal matches the ignition wire end being used. For fitment examples, this plug fits 1987-1993 Chevrolet Caprice, N/A; fits 1979-1985 Ford Capri, N/A; and fits 1982-1987 Dodge B150, N/A. Additional confirmed applications include 1978-1992 Pontiac Firebird, 1977-1985 Buick Regal, and 1979-1984 GMC K1500, N/A.

Quality Assurance

Champion is a long-established ignition brand, and the Copper Plus line is built around copper-core plug construction for controlled heat transfer and consistent electrical performance. The 25-1 is specified with nickel electrode materials, a resistor design, and a tapered seat to support proper service replacement in listed applications.