Champion 426 Spark Plug

Champion Copper Plus 426 Spark Plug Overview

Champion Copper Plus 426 is a spark plug built for dependable ignition performance and steady heat control. Its copper core electrode helps improve conductivity, while nickel center and ground electrode materials support consistent wear in everyday driving.

With the RC9YC5 plug type and a flat seat design, this Champion spark plug is a direct-match option for a wide range of Honda, Acura, Chrysler, Dodge, Mitsubishi, Jaguar, Toyota, and Chevrolet applications. It is a practical choice for drivers searching for a Champion 426 spark plug for Honda Civic, Acura Integra, or other OE-style secondary ignition service.

Key Features

• Copper core electrode for improved conductivity and heat management
• Nickel center electrode tip and nickel ground electrode core material
• Resistor design for reduced electrical noise
• Flat seat construction with 0.75 reach and 14 mm thread diameter
• Hex size 0.625 in. / 15.880 mm for standard service tools
• Champion Copper Plus line for OE-style ignition service
• Part number 426 with plug type RC9YC5

Product Details

The Champion Copper Plus line focuses on reliable everyday ignition performance with a copper core that helps transfer heat efficiently and maintain stable operation. This design supports good overall wear and is suited to vehicles that call for the RC9YC5 plug type. The Champion 426 spark plug is listed across multiple applications, including 2011-2016 Honda CR-Z, 1999-2000 Honda Civic, 1995-1999 Chrysler Sebring, 1995-1999 Dodge Avenger, 1997-1999 Mitsubishi Eclipse, 1995-2001 Acura Integra, and 1990-1992 Chevrolet Corvette.

This part cross-references Karlyn 784 for the same application.

What This Spark Plug Helps Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent spark delivery
• Misfire conditions related to aged secondary ignition components
• Reduced fuel efficiency from weak ignition performance
• Maintenance replacement for OE-style tune-up service

Installation Notes and Fitment Tips

Verify the vehicle’s required plug type, thread diameter, reach, seat type, and gap before installation. Fitment examples include Fits 2011-2016 Honda CR-Z, N/A; Fits 1995-2001 Acura Integra, N/A; Fits 1999-2000 Honda Civic, N/A; Fits 1995-1999 Chrysler Sebring, N/A; Fits 1997-1999 Mitsubishi Eclipse, N/A; and Fits 1990-1992 Chevrolet Corvette, N/A. Gap specifications vary by application, including 0.050 in., 0.052 in., 0.044 in., and 0.060 in., so confirm the vehicle-specific requirement before service. The non-removable nut terminal and hex design support standard spark plug service procedures.

Quality Assurance

Champion Copper Plus spark plugs are built to meet the demands of OE-style ignition service with materials selected for conductivity, heat control, and wear consistency. Part number 426 is engineered for direct application matching where RC9YC5 is specified.