MSD 31489 Super Conductor 8.5mm Spark Plug Wire Set Big Block Chevy Marine HEI Red

MSD's Super Conductor spark plug wire set (PN 31489) is engineered specifically for Big Block Chevy marine engines with HEI ignition systems. Reliability and performance are equally critical in demanding marine environments, and this wire set is purpose-built to meet both requirements. Wires are precut to exact specifications for a clean, bolt-on installation with no trimming required.

At the core of the Super Conductor design is a helically wound copper alloy conductor with an impressive 40 feet of conductor packed into every single foot of wire. This spiral-wound construction delivers resistance of less than 50 ohms per foot, maximizing spark energy delivered to the plug for a stronger, more consistent ignition event. A ferro-magnetic impregnated core acts as an EMI choke, suppressing radio frequency interference without sacrificing spark output.

Key Features:

• 8.5mm red jacket — protects against high heat and abrasion in the engine bay
• Extra-heavy fiberglass braid serves as a strong dielectric insulator
• DuPont Kevlar-reinforced core adds tensile strength and long-term durability
• Helically wound copper alloy conductor — less than 50 ohms/ft resistance for superior spark
• Ferro-magnetic impregnated core creates an EMI choke to eliminate interference
• Silicone and synthetic heat-resistant boots with 90-degree plug ends
• Dual Crimp terminals provide maximum connection strength and lock securely to the spark plug terminal
• HEI-style distributor cap terminal for direct fitment to HEI ignition systems
• Wires precut to exact specifications — true bolt-on installation
• CARB Executive Order compliant — legal for use on emissions-controlled vehicles

This set is specifically tailored for Big Block Chevy marine applications, delivering a factory-quality fit with performance-grade construction. The tough high-heat sleeve and dual-crimp terminal design make this wire set an ideal upgrade or replacement for any BBC marine engine running an HEI distributor.