Sierra 18-8813-1 MagForce Premium Marine Spark Plug Wire Set 4-Cylinder Thunderbolt Ignition

The Sierra 18-8813-1 MagForce Premium Marine Spark Plug Wire Set is a high-performance ignition wire set engineered specifically for marine applications. Built to meet or exceed OEM standards, this wire set delivers reliable spark delivery, superior RFI/EMI suppression, and long-lasting durability in the harsh marine environment. It replaces Volvo OEM part number 875571 / 875571-2 and is compatible with Thunderbolt-type ignition systems. The set uses 7mm (0.276") wire and includes a coil wire.

Key Features:

• MagForce Magnetic Suppression Core — Application-specific design for optimal spark delivery and ignition performance
• Kevlar® reinforced inner core — Ensures conductor integrity and provides maximum durability and long service life
• Durable stainless steel wound conductor — Delivers maximum horsepower and peak engine performance
• Premium silicone jacket and boots — High-tear-strength silicone protects to 500°F for ultimate high-temperature resistance
• Superior RFI/EMI suppression — Electronics-friendly design protects GPS, VHF, Loran, and other sensitive onboard electronics
• Corrosion-resistant stainless steel terminals — Spark plug and distributor terminals resist corrosion for maximum conductivity
• OE-style sealed boots — Provide a moisture, heat, and dirt barrier at every connection point
• Compatible with Thunderbolt-type ignition systems
• 7mm wire diameter — Includes coil wire
• OEM Replacement: Volvo 875571 / 875571-2

Sierra's MagForce wire sets are designed to work with any original equipment or aftermarket marine ignition system, making them an ideal choice for maintaining and restoring ignition performance on 4-cylinder marine engines.