TEFZEL Flying Lead Harness

This harness is built for customers who want a high-quality wiring solution using genuine motorsport-grade materials and prefer to complete the final terminations themselves. The loom is constructed entirely from (M22759/16) Tefzel wire, offering the strength, heat resistance and chemical durability required for modern motorsport applications.

It is suitable for engine conversions, standalone ECU installations and custom rewiring work where long-term reliability is essential. The ECU end of the harness is fully terminated using the correct connectors, while the opposite end is supplied with flying leads so you can route and finish the loom to suit your layout. 

Wire Construction

Tefzel wiring uses an ETFE insulation originally developed for high-temperature aircraft and avionics systems. ETFE offers excellent resistance to fuels, oils, solvents, and high-pH cleaners, while maintaining stability in continuous high-heat environments. Although the insulation wall is thin, it is extremely robust, allowing the harness to remain compact and lightweight without compromising abrasion resistance or mechanical strength. This makes it particularly well suited to racing, off-road and high-performance engines where space, heat and vibration are major considerations.

Included with Each Harness

• ECU connectors pre-installed and machine-pinned

• Cut-to-length Tefzel flying lead loom

• Shielded M27500 wiring for cam, crank and knock sensors

• K-type fibreglass thermal wire for EGT channels (where required)

• ECU pinout and colour-coding sheet available from the downloads section

ECU Compatibility

This harness can be supplied for most aftermarket ECUs, including Haltech, Link, Motec, MaxxECU, Emtron and others. If your ECU is not currently listed or supported, contact us, and we can develop a cut-to-length version specifically for your project.

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