RLP Spark Plug Wire Set for Chevy V8 HEI – 9-Piece 8.5mm Red High-Temp Silicone, Spiral-Wound Core

RLP's 8.5mm high-performance spark plug wire set is a universal HEI-compatible 9-piece kit (8 plug wires + 1 coil wire) engineered to deliver reliable ignition, heat resistance, and durable conductivity for Chevy small block and big block engines.

If you restore classic V8s or upgrade a street/strip build, the ignition wires you choose affect throttle response, consistency, and durability. This RLP kit uses a spiral-wound core, tightly woven fiberglass braid and heavy-duty silicone jackets to handle high voltages and elevated under-hood temperatures while providing corrosion-resistant terminals and 90-degree boots that fit most HEI distributors.

Which Chevy engines will these wires work with?

These wires are designed as a universal fit for HEI ignition systems on many Small Block and Big Block Chevy V8s. They cover common displacements and model families used in restorations, swaps, and high-performance builds.

• Fits SBC and BBC applications including popular sizes such as 302, 305, 327, 350, 400 and 348, 396, 427, 454, 502, etc.
• Compatible with HEI distributors and standard V8 layouts requiring 8 plug wires plus one coil lead.
• Works for performance and replacement use on engines with 4.9L–10.4L displacements listed in product specs.

How do these wires improve ignition performance and durability?

Performance comes from stable high-voltage transfer and protection from heat, oil, and abrasion. The combination of spiral-wound core and dielectric insulation reduces crossfire and energy loss while the silicone jacket and boots shield the internals from the engine environment.

• 8.5mm spiral-wound core for strong conductivity and reduced interference.
• High-dielectric insulator plus fiberglass braid for stability under load.
• Heavy-duty silicone jackets and high-temp boots resist oil, heat, and abrasion.

What hardware and installation features are included?

The kit ships complete with eight plug leads and one coil lead, pre-terminated with sturdy terminals and 90-degree boots to match HEI distributors. Terminals are metal combinations chosen to balance conductivity and corrosion resistance for long life.

• 9-piece set: 8 plug wires + 1 coil wire for HEI systems.
• Black 90° boots on both plug and coil ends for secure seating and clearance.
• Stainless steel and brass terminals for reliable electrical contact.

What warranty and quality assurances come with the set?

RLP provides a 12-month warranty backing the materials and workmanship of this replacement ignition wire set. The product is packaged new and inspected to meet quality-control standards for aftermarket ignition components.

• 100% brand-new, factory-packed wiring kit with quality inspection.
• 12-month warranty for replacement or refund if the product fails under normal use.
• Replaces part number SP10-390-1010 and matches HEI-style boot geometry.

Who this is for: Enthusiasts rebuilding Chevy Small Block or Big Block V8s, hobby mechanics swapping to HEI distributors, and street/performance drivers who want a rugged, heat-resistant ignition wire set that balances conductivity and durability. Choose this RLP 8.5mm kit when you need a universal, HEI-compatible replacement that simplifies installation and helps maintain stable ignition under demanding conditions.