TOYOTA SUPRA 2JZ MK4
In our workshop, we are currently working on one of those projects that particularly excite us – a Toyota Supra MK4 with the legendary 2JZ engine, undergoing a complete electrical transformation.
The project's goal is not just to replace the ECU, but to create an entirely new motorsport electrical installation that will meet the demands of serious road and competitive use.
Many cars reaching an impressive tuning level of 700, 800, or more horsepower still use the factory wiring, sometimes more than 25 years old. Regardless of the quality of the original Toyota electronics, years, heat, vibrations, and numerous previous modifications leave their mark on every system.
That's why we decided to start from scratch.
Completely new installation
The MaxxECU RACE ECU is used for engine management, and the complete installation is built from scratch according to motorsport standards.
As the base for the electrical installation, we use the wire set provided by MAXXECU, while for all additional lines, we use Tefzel (ETFE) wires, which are standard in the aerospace and motorsport industries. Compared to classic automotive conductors, Tefzel offers greater resistance to temperature, chemicals, abrasion, and vibrations, with less mass and a thinner outer diameter, allowing for the creation of a more compact and reliable installation.
We use Raychem DR-25 protective sleeving, which provides exceptional resistance to temperature, chemicals, and mechanical damage. The ends of the installation are sealed with Raychem shrink boots to ensure maximum protection against moisture, oil, and external influences.
For connections, we use proven Deutsch DT and DTM connectors, while all connectors directly on the engine have been replaced with new OEM Toyota connectors. This maintains factory connection quality on all sensors and actuators, without compromise.
Concentric twisting – how to make a proper motorsport installation
One of the things that differentiates a serious motorsport installation from a classic modification is the method of creating the wiring harness itself.
Instead of routing conductors in parallel, all wires are arranged and twisted using a concentric method. This approach results in a more compact harness, more even stress distribution, and better resistance to vibrations.
After assembly, the conductors are secured with Kevlar and Kapton tapes before final sheathing in DR-25 protection.
This method of construction requires significantly more time and planning, but the result is an installation used in professional motorsport.
Why do everything from scratch?
In projects of this level, the electrical installation becomes as important as the engine, turbo, or fuel system.
A faulty connection, poorly executed branching, or old wiring often cause problems that are difficult to diagnose later. That's why every conductor, connection, and connector on this project undergoes detailed planning and execution.
The result is a reliable system that allows for easier maintenance, simpler future upgrades, and safer vehicle operation in all conditions.
BP OPREMA I SERVIS
In addition to offering parts for performance and motorsport projects, we also build complete electrical installations in our workshop for vehicles of all preparation levels – from street builds to serious competition cars.
If you are planning a STAND ALONE conversion, new installation, motorsport electronics, or a complete custom project, feel free to contact us.
Below are a few photos of the construction of this Toyota Supra MK4 installation and details of the process that are rarely seen after the car is finished.
