Moroso Spark Plug Wire

Moroso Spark Plug Wires: Built by Racers, for Racers

When it comes to ignition performance, few names carry as much credibility on the track as Moroso. Moroso has more than 50 years of experience supplying spark plug wires to the top teams of NASCAR and NHRA, as well as auto manufacturers. That deep racing heritage is baked into every wire set they produce — and it shows in the engineering details that separate their products from generic replacements.

Moroso offers a wide range of spark plug ignition wires to fit your needs, all made in the U.S.A. at Moroso Wire Technologies in Philadelphia, PA. Their Blue Max, Ultra, Ultra 40, and Mag Tune wires offer solutions for your ignition wire needs in a variety of configurations and price points, from pre-made direct fit kits to universal DIY kits. Whether you're wrenching on a weekend cruiser or building a full-blown race engine, there's a Moroso spark plug wire solution engineered specifically for your application.

The Ultra 40: Moroso's Race-Ready Flagship Wire

At the top of the lineup sits the legendary Ultra 40. Features of these 8.65mm wires include a Kevlar® core that's four times stronger than Aramid cores, a class-leading 40 ohms of resistance per foot, nickel copper alloy conductors for superior spark energy transfer, an extra-thick EPDM layer for greater dielectric strength, high-temperature silicone boots that can withstand heat up to 600 degrees, and locking stainless steel plug terminals. Their closely woven fiberglass, silicone-impregnated insulation provides up to 8,000 extra volts of protection, and the extra-thick diameter extends wire life by adding additional insulation against heat, chaffing, and contaminants.

The Ultra 40 incorporates a spiral-wound nickel/copper alloy conductor wrapped at the optimum ratio to produce the highest level of spark energy while producing the lowest level of electromagnetic and radio frequency interference. For builders routing wires near exhaust headers — a common challenge with performance builds — sleeved versions extend spark plug life and protect against exhaust header heat, chaffing, and contaminants, while also adding extra dielectric strength.

Blue Max & Mag Tune: Solid-Core Solutions

The famous "Blue Max" 8mm and "Super Max" 11mm Spiral Core ignition wire specifications were conceived and designed by Moroso engineers using the latest technology and finest materials obtainable. Moroso Blue Max solid core wire rolls are designed for super high-performance engines for race use only and are engineered for magneto and other ignition systems that do not require electromagnetic interference suppression. The specially designed combination silver-plated copper and stainless steel solid core provides maximum conductivity and strength, and each roll is individually tested for continuity after termination to ensure race-ready performance.

The Moroso Ultra: Street-Smart Performance

For street and mild performance builds, the Moroso Ultra series delivers excellent value. Moroso Ultra ignition wire sets are equal to or exceed OEM specifications, depending on the application, without the dealer prices. The efficient conductor is constructed with stainless nickel alloy wire, wound 32 times per inch around a conductive, latex-coated, heavy fiberglass core. The outer jacket is made from two layers of high-heat resistant EPDM separated by a nylon reinforcing pull tape for added pull strength, while silicone plug boots protect against high-heat situations and encase sure-grip, snap-lock terminals for positive connections.

Application Coverage and Fitment

Moroso's spark plug wire catalog spans an impressive range of platforms. Sets are available for small block and big block Chevrolet — including dedicated under-header routing versions — Ford applications including the 289/302 and 351W, GM LS and LT series engines, and universal cut-to-length kits for custom builds. Sets are available in different thicknesses and colors, assembled or not, with multiple boot end angles. Boot angles of 90°, 135°, and straight configurations are offered across the lineup to handle virtually any header or engine bay geometry.