Ultra 40 Plug Wire Set - BBC HEI

The Moroso Ultra 40 Plug Wire Set for big block Chevy HEI distributors is designed for high-performance applications, ensuring reliable spark plug wire functionality for engines operating under sustained load and high RPM conditions. This eight-cylinder plug wire kit is ideal for builders, restoration shops, and enthusiasts looking to upgrade ignition systems on both carbureted and fuel-injected engines.

Featuring spiral core construction and a wire diameter of 8.65 mm, this set minimizes electromagnetic interference while maintaining signal integrity across the power band. The 90-degree plug boots provide secure connections in tight engine bay configurations, and the HEI-style terminal interfaces directly with modern ignition systems without the need for adapters. The under-header routing design accommodates tight clearances found in many big block Chevy installations.

With black insulation that resists UV degradation, the Ultra 40 set maintains its appearance even in engine bays exposed to prolonged sun exposure. Weighing 2.37 lbs, this complete wire set installs without requiring supplemental supports or rerouting existing engine components, making it a practical choice for anyone transitioning from points-based ignition to HEI or replacing worn original equipment wires.