EFI Customs

08/04/2025

Heres a sneak peek of our custom ignition harness, that we previously featured, installed on the customer's snazzy looking, freshly rebuilt M20.

We can't wait to see this engine in action and will post more follow-up photos and videos as they progress with the restoration of their E30.

If you're looking for a refresh or a completely new engine harness, don't hesitate to message us with some details!

25/03/2025

New products just in!

Reproduction coding plugs for E30 instrument clusters that allow you to have the correct tachometer readout after an engine swap.

We're stocking coding plugs for the following configurations:
6 Cylinder - 7000rpm
8 Cylinder - 7000rpm

Priced at $80 + shipping, get them while stocks last!

24/03/2025

VR Conditioners are back in stock!

Based on the V3.1 reference design from Speeduino, we've tweaked the layout to be a little bit more friendly with soldering access and less likely to interfere with other components on the ECU board.

Utilising a MAX9926 chip, this is capable of converting two VR inputs (one for crank, one for cam).

Get them while stocks last!

23/03/2025

It's been a busy few months designing a new ECU for Motronic 1.3 cars—and we're getting close to testing!

Inspired by the Speeduino V0.4.d and Raku V2.2 ECU designs, we've converted the layout to surface-mount components while keeping a few solderable options for custom implementations, like smart coils.

Key Features:
-️ Future-proofed design – Easier part replacements when components become obsolete
-️ Fully sequential injection & paired ignition (with a cam sensor)
-️ More I/O & cleaner installs – Integrated custom wiring into the 55-pin ECU connector

We’ll be putting this ECU through its paces in our E30 over the next few weeks to ensure it handles daily duties. A full production release will follow soon after!

Stay tuned for updates!

22/03/2025

New products just in!

We've partnered with Grooty of Grooty's Race & Resto out of South Australia to bring to you a new product, with more to come.

Designed and engineered in Australia, these TPS adapters are compatible with M10, M20, M30, M88 engines and more.

Priced at $50 + shipping, get one fresh off the press!

Manufactured in South Australia by Grooty of Grooty’s Race & Resto. These adapters are compatible with a variety of BMW engines including M10, M20, M30, M88 and more. Due to their design, they’re also compatible with other engines. If you have another engine and are unsure of compatibility

22/03/2025

We were recently tasked with performing a full restoration and modification to a Motronic 1.3 engine harness to suit a restomod E30 with a 2.5 M20, soon to be running on one of our ECU's.

Overall, the wiring harness started out quite tired and had many instances of wires hanging on by their last threads right next to their respective plugs.

The entire harness underwent a thorough electrical diagnosis, clean, repair and rewrap using TESA 51036 cloth tape.

Next, we modified the fuel injector harness to suit the semi-sequential injection that the customer will be running, which is all terminated using a Deutsch 8-pin connector.

Lastly, we designed and assembled a coil-on-plug harness to suit VAG R8 coils, which routes and terminates in the same area as the injector harness. For this we used TXL wire and finished with PPS sleeving to ensure its capable of withstanding the higher temperatures being so close to the exhaust manifold

All the new wiring was then integrated into the engine harness and carefully designed to suit the ECU perfectly.

If your engine harness needs attention or a full restoration, don’t hesitate to reach out. We're here to help get your vehicle running at its best.

17/01/2025

Here’s a look at a recent engine harness repair, re-wrap, and modification we completed. We carefully addressed the issues, integrated new sensor wires into the main loom and shortened the C101 plug for a better fit.

If your engine harness needs attention, don’t hesitate to reach out. We're here to help get your vehicle running at its best.

Send a message to learn more

11/11/2024

We’re excited to announce the arrival of the Bustoms M20 Crank Position Conversion Kit on our website. This complete kit is designed to make converting your Jetronic M20 engine to Motronic — or a standalone ECU — easier than ever.

The kit includes:
- Crank pulley ring (welding required)
- Crank position sensor mount
- Sensor, connectors, boots, and mounting hardware

We’re also featuring a detailed guide on converting your Jetronic engine to Motronic, developed in collaboration with Bustoms to help you get the most out of this upgrade.

- Our store listing: https://www.eficustoms.com.au/shop/p/bustoms-m20-crank-position-conversion-kit

- Please visit Bustoms here: https://bustoms.au/ or on Instagram: https://www.instagram.com/bustoms.au

- You can find our conversion guide here: https://github.com/EFI-Customs/Motronic-1.3-Speeduino-Compatible-Project/blob/main/Jetronic%20To%20Motronic%20Conversion.md

Ready to make the switch? Visit our website for all the details.

29/09/2024

We’ve officially settled into our new location, and what better way to kick things off than with an ECU assembly!

This particular unit is headed to VIC, starting out in a 2.5L turbo M50, and will eventually be paired with a 3.0L turbo featuring Audi R8 coils. The customer opted for an STM32 controller, which will interface seamlessly with a digital dash via the onboard CANbus.

Whether you need a custom ECU, wiring solutions, or individual components, consider EFI Customs for your next project!

27/06/2024

Exciting update!

We will now be offering 3D printing products! We'll start off with enclosures, vent gauge pods, and eventually parts for odd bits that may be hard to get replacements for.

Also, we're excited to announce that our ECU enclosures will soon be in production. High-quality and built to last!

Our good friend, Aleksandar, designed the new enclosure and you can find his details here: https://www.linkedin.com/in/aleksandar-miletic/

Stay tuned for more updates and feel free to reach out with any questions.

30/04/2024

🚗 Exciting News Alert! 🚗

Introducing our latest service: Engine Harness Wrapping!

Is your vehicle in need of some TLC for its wiring system? Look no further! Our meticulous Engine Harness Wrapping Service ensures your engine's vital components are protected for the long haul. Using top-quality Tesa 51036 tape, we shield against heat, moisture, and abrasion, guaranteeing reliability mile after mile.

Plus, for just an additional $50, opt for an electrical inspection/diagnosis for added peace of mind. And don't forget, we offer repairs for harnesses sent for wrapping starting at an initial cost of $50!

Ready to give your car the care it deserves?
Contact us today or order the service directly at our website by following the link below!

Revitalize your vehicle's wiring system with our comprehensive Engine Harness Wrapping Service. Each harness undergoes a meticulous process: Removal of the old sheathing, Physical inspection, and Degreasing/cleaning Finally, we wrap it using industry-leading Tesa 51036 tape, known for i

17/03/2024

First mock-up of the E28Goodies R8 coil bracket.
Most of the time was spent cleaning and rearranging wires.

Next steps are to mock up the coil wires, rip the harness out and integrate new wires into it.

As you can see the battery tray is a bit of a mess which we plan to clean up by removing old and unnecessary wires from the Motronic harness and by implementing a distribution bar for the positive wires. The initial plan is to mount it on the firewall in the battery tray but time will tell if that ends up looking neat.

As always, if you're planning to take the dive into standalone engine management, need wiring done or just want general build advice please don't hesitate to reach out.