Bespoke wiring harnesses designed around the build.
From standalone ECU conversions and engine swaps to clubsport and full motorsport harnesses, we design and build reliable wiring systems with serviceability, diagnostics and long-term support in mind.
A custom wiring harness is more than a bundle of wires.
Wiring is the nervous system of the build. If a bespoke wiring harness is badly planned, poorly routed or difficult to diagnose later, the car becomes unreliable before it even reaches calibration.
We design wiring harnesses around the ECU, sensors, power distribution, CAN devices and future serviceability. Whether it is a clubsport harness or a full motorsport loom, the goal is the same: a reliable installation that works properly and can be supported later.
From wiring repairs to full bespoke wiring harnesses.
Whether you need a complete standalone ECU wiring harness, MaxxECU integration, clubsport wiring support or help fixing an existing electrical issue, we can support the job properly.
Motorsport Harnesses
Professional motorsport harnesses using concentric twisting, DR25 sleeving, Raychem boots, potting, labelling and appropriate termination for demanding applications.
Road & Clubsport Harnesses
Bespoke clubsport wiring harnesses using heatshrink sleeving, Raychem ATUM / SCL boots, proper labelling and reliable construction for serious road and track builds.
Fault Finding & Support
Sensor wiring, CANbus issues, remote diagnostics, relay and fuse circuits, connector repairs, wiring health checks and trackside support where required.
Designed around the ECU, the car and the intended use.
- MaxxECU and standalone ECU wiring harness design
- Custom engine loom builds, modifications and repairs
- Sensor wiring, calibration inputs and shielded wiring
- CANbus wiring, termination and module integration
- PDM, dash, keypad and expansion module wiring
- Relay, fuse, fan, fuel pump and power circuits
- Battery relocation, starter and alternator wiring
- Custom HT leads, sensor potting and motorsport finishing
How a bespoke wiring project normally works.
The best bespoke wiring harnesses are planned before anything is cut, stripped or terminated.
Spec the job
We confirm the ECU, sensors, devices, power requirements and what the harness needs to control.
Design and build
Routing, branches, connector choices, pinouts and protection are planned around the car.
Test and support
The harness is checked before installation, then supported through setup, first start, remote diagnostics and calibration.
Your wiring information, available whenever you need it.
Every bespoke wiring harness we build includes access to our secure vehicle and wiring portal, giving you a permanent place to access the important files connected with your project.
- View your wiring diagram from a phone, tablet or computer
- Download the latest wiring diagrams whenever required
- Re-download ECU map files and supporting project documents
- Keep the key information for the vehicle together in one place
Whether you are in the workshop, away at an event or returning to the vehicle years later, the information remains available when you need it.
Recent wiring work.
A look at the sort of wiring, loom building and installation work we carry out.
Not every job needs a full harness.
Not every project needs a full bespoke wiring harness. We also help with the smaller electrical jobs that make the car safer, cleaner and easier to support.
Common questions.
What ECUs do you build looms for?
We mainly support MaxxECU, but can support most standalone ECU wiring and ECU integration projects depending on the job.
What is the booking process?
The booking process depends on the type of project and how involved the wiring work needs to be.
For clubsport harnesses and standalone ECU wiring projects, we can often assess the job from a sensor list, build specification, photos or an in-person discussion. Once we understand the scope, we provide an estimate and, if approved, schedule the work into our calendar.
Motorsport harnesses are usually more involved and require more planning before an accurate estimate can be provided. This can include inspecting the vehicle, planning the loom layout, discussing expectations, defining requirements and working through an approximate bill of materials.
Once the scope is agreed, the project can be booked in and moved into the build phase.
What do your estimates involve?
When estimating a wiring project, we generally assume there is reasonable access for harness installation and routing.
Additional labour may be required if interior components need removing and refitting, carpets need lifting, firewalls require modification, holes need adding for loom pass-throughs, or access is restricted. Depending on the vehicle, this process can become very time consuming.
It is important to consider where the wiring needs to run from and to, and whether access has been prepared beforehand. This can include items such as seats, dashboards, centre consoles, carpets and trim panels.
Are modern street cars more difficult to wire?
Modern street cars can be significantly more complicated than older vehicles when it comes to wiring installation.
Access is often more restricted, interior removal can be more involved, and wiring routes may be harder to reach without removing seats, carpets, trim panels, dashboards or other components. Modern vehicles may also have more factory electronics, modules and safety systems to work around.
Because of this, installing a wiring harness into a modern road car can involve a significant number of additional labour hours compared with an older or more stripped-out vehicle.
How long does a wiring project usually take?
Turnaround time depends on the size of the harness, the complexity of the vehicle, parts availability and the overall scope of work.
As a guide, a clubsport harness can often take around 1–3 weeks depending on size and complexity. Full motorsport harness projects can take longer, often around 1–2 months depending on the level of design, materials, installation and support required.
We will always discuss expected timescales during the quoting and booking process, and we will keep you updated if anything changes during the project.
Do you install the harness or just build it?
Both. We can build only, install only, or handle the full wiring and setup process depending on the project.
Can I supply my own connectors?
We would generally advise against it.
More often than not, supplied connectors turn out to be cheap Chinese replicas, incorrect for the application, or supplied with mismatched components. Common issues include incorrect terminal sizing for the wire being used, incorrect wire seals, or terminals that do not actually accept the supplied seals despite being sold together.
We keep a large range of genuine OE connectors, terminals and seals in stock to ensure proper fitment, reliability and long-term serviceability.
Can I supply my own sensors, ECU, dash or PDM?
Yes, but we may need to inspect supplied parts before confirming they are suitable for the job.
Where possible, please supply genuine parts, correct documentation, connector kits, pinout information and any manufacturer wiring data. Incorrect, missing or unknown parts can slow the project down and may affect the final cost.
If we believe a supplied item is unsuitable, unreliable or likely to cause issues later, we will advise before using it.
Do you install electronics and supporting hardware?
Yes, depending on the project. We can help install ECUs, dashes, PDMs, keypads, sensors and related electrical hardware as part of a wiring project.
Some installations require custom mounting solutions, brackets or integration work. Where needed, we can support this with design work, 3D scanning, 3D printing or CNC-machined parts depending on the requirements.
Can you integrate dashes, CAN devices or PDMs?
Yes. We can help with CANbus wiring, dash displays, PDMs, keypads, expansion modules and related control wiring.
Can you repair or modify an existing wiring harness?
Yes, if the harness is suitable to work with. We can inspect, repair, re-terminate, simplify or modify existing wiring.
Can you work from a wiring diagram or pinout I already have?
Yes. Existing wiring diagrams, ECU pinouts, sensor information and previous build notes are always useful.
However, diagrams and pinouts still need to be checked against the actual components and vehicle. Incorrect or outdated information can lead to faults, so we always verify critical circuits before building or modifying a harness.
Do you offer remote or trackside support?
Yes. Depending on the project, we can provide remote diagnostics, technical support and trackside assistance alongside installation and calibration work.
What does my vehicle need before drop-off?
Vehicles should arrive in a condition that allows the agreed wiring work to begin efficiently.
Any areas requiring wiring access should be accessible, and any electronics or components that need to be mounted should either be supplied, fitted or clearly positioned if previously agreed.
If additional disassembly, preparation, fabrication or access work is required beyond the agreed scope, this may affect the project timeline and final cost.
Need wiring support for your project?
Tell us about the car, ECU, sensors and what you need the harness to do. Whether it is clubsport wiring, motorsport harness construction, MaxxECU integration or fault finding, we will help you work out the right approach.
