Wiring Supplies

Buy Motorsport Wiring Supplies in Australia

Wire and connectors get the glory, but the consumables decide whether a harness looks and lasts like a professional build: the tapes that hold the twist, the splices inside the bundle, the sleeving over it and the epoxy that keeps the boots sealed. 12Volt Motorsports stocks the same supplies we use on our own customer harnesses, Tesa, TE, ResinTech and quality generics, in Melbourne, shipped Australia-wide.

The Consumables That Make a Harness

Every professional loom uses the same small kit. Polyimide tape holds wires as the concentric twist grows. TE open barrel splices make the joins inside the bundle, crimped and inspectable rather than twisted and taped. OEM harness tapes wrap the finished runs, cloth in the engine bay, fleece in the cabin. Braid or DR25 goes over the top, and where boots meet sleeving, a bead of RT125 epoxy seals the deal. None of it is expensive, and all of it is the difference between a loom that lasts a season and one that lasts the car.

Wiring Supplies at a Glance

OEM Tapes and the PVC Tape Problem

The black PVC tape from the hardware store is the enemy of a good loom. It softens with heat, creeps, unwinds and leaves adhesive on every wire it touched. Factory harnesses are wrapped in purpose made tapes instead: Tesa 51036 cloth in the engine bay, rated to 150 degrees with serious abrasion resistance, and Tesa 51608 fleece inside the cabin, where its job is bundling plus silencing rattles against trim. Same tapes the European manufacturers use on the production line, sold here by the roll.

Where These Fit in a Harness Build

Lay out the wires and the polyimide tape starts working immediately, holding each layer of the concentric twist as it grows. Joins inside the bundle get an open barrel splice sized by CMA and sealed under Sumitomo W5DL. The finished runs get wrapped in Tesa or sleeved in DR25, with braid on the street car runs that just need tidying and protection. And where a Raychem boot meets the sleeve, RT125 epoxy bonds it into a sealed, permanent finish. On the power side, tinned copper lugs terminate the battery cables, hex crimped and sealed, landing on insulated distribution posts for clean central power and ground points. Terminate it all with the right wiring tools and the loom is built once, properly.

Learn With Our Free Guides and Calculators

Every guide and calculator we publish comes from the same bench these supplies live on.

Browse the Wiring Resources Library

Use the Concentric Twist Calculator

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Frequently Asked Questions

Where can I buy motorsport wiring supplies in Australia?

12Volt Motorsports stocks harness tapes, TE open barrel splices, braided sleeving and ResinTech epoxy in Melbourne, shipped Australia-wide, the same consumables we build our own custom harnesses with.

Why not just use normal PVC electrical tape on a loom?

PVC tape goes gummy with heat, unwinds over time and leaves glue on everything. OEM harness tapes like Tesa 51036 and 51608 use heat rated carriers and adhesives designed to stay put for the life of the car, which is why every factory loom is wrapped in them and none are wrapped in PVC.

What is the difference between Tesa 51036 and 51608?

51036 is a cloth tape rated to 150 degrees for engine bay wrapping and abrasion resistance. 51608 is a soft fleece tape for interior looms, its job is bundling plus killing rattles where the loom touches trim. Engine bay gets cloth, cabin gets fleece.

How do I pick the right open barrel splice size?

Add up the circular mil area of every wire entering the splice and pick the splice whose CMA range covers the total. Each splice product page lists its CMA range and the CMA of common Tefzel gauges, and the sizing method is explained on each page.

What is polyimide tape used for in harness building?

Kapton type polyimide tape holds bundles and wraps branch points before sleeving goes on. It is thin, rated to around 260 degrees, and removes cleanly, which makes it the working tape of a concentric twist build, the one you wrap as you go.

When should I use braided sleeving instead of DR25?

Braid gives abrasion protection and a tidy finish with easy installation over connectors, good for interior runs, battery cables and street car work. DR25 gives a sealed, fluid resistant covering and is the motorsport standard for engine bay and chassis looms. Race harnesses get DR25, general tidy ups get braid.

What is ResinTech RT125 for?

Bonding Raychem System 25 boots to DR25 and connector backshells. The epoxy fills and seals the joint to IP68 and holds the boot in place under heat and vibration, the difference between a boot that stays sealed and one that slides off in a season.

Do the splices come in packs?

Yes, every splice size sells in packs of 10, 20, 50 or 100, with the 100 pack the cheapest per splice for harness builders.

What size battery lug do I need?

Match the lug to the cable cross section, 10 to 50mm2, then match the hole to the stud it lands on: M6, M8 or M10. Size the cable itself with our battery cable size guide, the lug follows the cable.

Do you ship wiring supplies Australia-wide?

Yes. Melbourne stock, shipped to Sydney, Brisbane, Adelaide, Perth, Canberra, Hobart, Darwin and everywhere in between, usually same or next business day.

Related Products and Resources

Need Advice?

Building your first proper loom and not sure what consumables you need? Call us on 0458 102 134 or email 12voltmotorsports@gmail.com with the job and we will put the kit together.