Moroso 73804 Ultra Race Spark Plug Wire Set Universal - 40 8.65mm

The Moroso Ultra 40 Race Spark Plug Wire Set is engineered for serious performance and racing applications, delivering maximum spark energy transfer with superior EMI/RFI suppression. At 40 ohms of resistance per foot, the spiral-wound nickel/copper alloy conductor is wrapped at the optimum ratio to push the highest level of spark energy to the plugs while keeping electromagnetic and radio frequency interference to an absolute minimum.

The multi-layer construction starts with a Kevlar center core that is four times stronger than standard aramid fiber cores, reducing center diameter while increasing surrounding insulation for greater dielectric strength and tensile durability. A conductive polymer coating and ferrite-impregnated core work together to further suppress interference across the ignition system.

Outer protection is equally impressive. A silicone jacket shields against exhaust header heat, chafing, and contaminants, while closely woven fiberglass impregnated with high-voltage-leak-resistant silicone adds up to 8,000 volts of extra insulation. High-temperature silicone boots withstand heat up to 600°F, and locking stainless steel terminals with fold-over crimping ensure a secure, corrosion-resistant connection at every plug.

Key Features:

• 8.65mm diameter spiral core construction
• 40 ohms resistance per foot for optimized spark energy and EMI/RFI suppression
• Spiral-wound nickel/copper alloy conductor for maximum spark transfer
• Kevlar center core — 4× stronger than standard aramid fiber cores
• Ferrite-impregnated core for added interference suppression
• Conductive polymer coating
• Closely woven fiberglass with silicone impregnation — up to 8,000V extra insulation
• Extra-thick EPDM layer for greater dielectric strength
• Silicone jacket protects against heat, chafing, and contaminants
• High-temperature silicone boots rated to 600°F
• Locking stainless steel terminals with fold-over crimping

Trusted across the highest levels of motorsport — from dual-mag Top Fuel dragsters to NASCAR Cup Series — the Moroso Ultra 40 is the benchmark in high-performance ignition wiring.