Question 1

What is Tefzel wire and why is it used in motorsport wiring?

Accepted Answer

Tefzel is a brand name for ETFE (Ethylene Tetrafluoroethylene) fluoropolymer wire. It is the go-to wire for professional motorsport and aerospace wiring because it is rated to 150C, 600V, and has exceptional resistance to fuels, oils and chemicals. It is also significantly lighter and more flexible than standard automotive wire at the same gauge, making it ideal for weight-sensitive race car applications.

Question 2

What AWG wire should I use for my engine management wiring?

Accepted Answer

For most ECU signal wiring including sensors, triggers and outputs, 20 or 22 AWG Tefzel is standard. For injector and coil wiring, 18 AWG is commonly used. For power feeds, fuel pumps and high current circuits, 16 AWG or heavier is recommended.

Question 3

What is the difference between Deutsch DTM, DT and DTP connectors?

Accepted Answer

The DTM series is a miniature waterproof connector rated to 7.5A per pin, ideal for ECU signal wiring and sensors. The DT series is larger, rated to 13A per pin, and is the most widely used connector in motorsport wiring harnesses. The DTP series is a high current connector rated to 25A per pin, used for fuel pumps, fans and other high draw applications.

Question 4

What is Raychem DR-25 and why is it used instead of standard heatshrink?

Accepted Answer

Raychem DR-25 is a military specification heatshrink tubing rated to 150C with a 2:1 shrink ratio. Unlike standard heatshrink, DR-25 is flame retardant and resistant to fuels, hydraulic fluids, lubricating oils and aviation fuels. It is the industry standard for motorsport and aerospace wiring harness sleeving.

Question 5

Should I solder or crimp my motorsport wiring connections?

Accepted Answer

Crimp every time. Soldering is actively discouraged in professional motorsport wiring because solder creates a hard point in the wire that can crack and fail under the constant vibration of a race car. A correctly executed crimp with the proper tool creates a gas-tight cold weld between the wire strands and the terminal.

Question 6

What is a PDM and do I need one?

Accepted Answer

A PDM (Power Distribution Module) replaces traditional fuse boxes and relay panels with a single programmable device. It controls all switched outputs in the vehicle, provides overcurrent protection, and integrates with your ECU for data logging and diagnostics. PDMs save weight, reduce wiring complexity and make fault finding much easier.

Question 7

How long does a full vehicle rewire take?

Accepted Answer

A full vehicle rewire at 12Volt Motorsports typically takes between 2 and 6 weeks depending on the complexity of the build, the number of systems involved and the level of finish required. Simple engine bay rewires with a new ECU can be completed faster. Contact us early to discuss your project and timeline.

Question 8

Do you ship parts Australia wide?

Accepted Answer

Yes. We ship all products Australia wide. Most in-stock orders are dispatched within 1-3 business days. We stock genuine Haltech, Deutsch, Raychem and Tefzel products so what you see on the website is what we use in our own builds.

Question 9

Does an aftermarket ECU make my car more powerful?

Accepted Answer

Not by itself. An ECU is not a power adder. What it does is give a professional tuner the ability to precisely calibrate your engine's fuel delivery, ignition timing, boost control and cam timing to extract the full potential from your existing setup. The power gains come from the quality of the tune, not from the ECU alone.

Question 10

Which ECU brand should I choose for my build?

Accepted Answer

Haltech is our primary recommendation for most Australian performance builds. Motec suits professional motorsport at the highest level. Emtron is an Australian-made ECU sitting between Haltech and Motec. Holley EFI suits American V8 applications. FuelTech is the preferred choice for serious drag racing. Contact us on 0458 102 134 to discuss which suits your specific build.

Question 11

What is flex fuel and can my ECU run it?

Accepted Answer

Flex fuel means the ECU can automatically adjust fuelling and ignition timing on the fly depending on how much ethanol is in the fuel, so you can run anywhere from standard 98 octane petrol to E85 or any blend without re-tuning. All current Haltech, Emtron, Motec, Holley and FuelTech ECUs support flex fuel with the addition of an ethanol content sensor.

Question 12

Can you install an aftermarket ECU on any car?

Accepted Answer

Most wire-in ECUs from Haltech, Motec, Emtron, Holley and FuelTech can be fitted to any vehicle with a custom wiring harness. Haltech also makes plug-in ECUs for popular platforms including Nissan Skyline R32/R33/R34, Mazda RX-8 and GM LS engines. We build custom harnesses for all makes and models.

Motorsport Wiring Resources

Souriau 8STA Connector Resources

Tefzel Wire Reference

Raychem DR25 Size Guide

Heatshrink Selection Guide

Battery Cable Size Guide

Pressure Sensor Reference Guide

Motorsport Harness Materials Checklist

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