Understanding the Differences Between Standard Automotive Wiring and High-Performance ETFE Harnesses

When people upgrade performance parts on a race car, they usually think about engines, suspension, or aerodynamics. Wiring is rarely the first thing that comes to mind — yet it’s one of the most important systems in the entire vehicle.

Your wiring loom controls ignition, fuel delivery, sensors, communications, and safety systems. If it fails, the car stops. Because of this, understanding the differences between wiring materials can help builders make better decisions about reliability, durability, and system performance.

Why Wiring Material Matters

Not all automotive wire is built for the same purpose. Standard road-car wiring is designed primarily for:

• cost efficiency

• mass production

• long-term road use in moderate environments

High-performance or motorsport wiring, however, is often required to withstand:

• elevated temperatures

• constant vibration

• fluid exposure

• tight packaging

• rapid servicing

The insulation material used on the conductor plays a major role in determining how well the wiring handles these conditions.

What Is ETFE-Insulated Wire?

One commonly used material in high-reliability harnesses is ETFE (Ethylene Tetrafluoroethylene) insulation manufactured to M22759-series specifications.

Compared with many standard automotive wire types, ETFE insulation typically provides:

• higher temperature tolerance

• strong abrasion resistance

• resistance to fuels, oils, and solvents

• thin insulation walls

• high dielectric strength

Because the insulation can be thinner while maintaining durability, ETFE wiring is often smaller in diameter and lighter than many conventional automotive wires.

Terminology note: “Tefzel®” is a registered trademark of The Chemours Company. ETFE is the correct generic material name for this insulation type.

Typical Comparison of Wire Types

Note: Exact values vary depending on manufacturer and specification.

Reliability Considerations in Performance Vehicles

In high-stress environments such as motorsport or off-road racing, wiring systems experience much harsher conditions than typical road vehicles. Over time, insulation can degrade, connections can loosen, and conductors can fatigue if materials aren’t suited to the environment.

Using materials designed for demanding applications can help reduce risks such as:

• insulation breakdown

• signal interference

• connector failure

• electrical shorts

Material choice alone doesn’t guarantee reliability, however. Harness design, routing, strain relief, and termination quality are equally important.

Why Smaller, Lighter Wiring Can Be Beneficial

Reducing wiring size and mass isn’t just about saving weight — it also affects packaging and serviceability.

More compact wiring can allow:

• tighter routing in restricted areas

• improved airflow around components

• easier access during maintenance

• cleaner installation layouts

For vehicles with limited space, such as formula cars, motorcycle-engine builds, or compact race chassis, efficient wiring design can make a noticeable difference in how easily systems can be installed and serviced.

A Note on Industry Usage

High-reliability wire types such as M22759-series ETFE are commonly used in industries where system failure is not acceptable, including:

• aerospace

• defence systems

• professional motorsport

• industrial machinery

Their use in these sectors is primarily due to durability, stability, and predictable performance under demanding conditions.

Key Takeaway

Wiring may not be the most visible part of a vehicle build, but it is one of the most important. The type of wire used — along with harness design and construction quality — plays a significant role in long-term electrical reliability and ease of maintenance.

Understanding the differences between insulation materials helps builders choose wiring systems that are appropriate for their environment, whether that’s a daily-driven street car, a track car, or a full competition vehicle.