Custom Diesel CalibrationEngineered from the Code Up
Down Under Performance was built by diesel enthusiasts who live and breathe the machines we tune. Our team combines hands-on racing experience with deep technical engineering — the kind that comes from years spent inside the software that controls modern engines.
Every member of our team has over a decade of experience in their field
— from professional diesel racing to advanced control system authoring. Our team has a diverse background: some are primarily automotive engineers, others mix both calibration and racing experience.
Things like years spent Pro-Modified NHDRA racing, and being top calibrators on Motec and other standalone ECUs. The rest of us come from the software and reverse-engineering side, specializing in Bosch/GM systems.
We study the firmware itself — not just the calibrations — to understand how every line of code makes the engine behave. That knowledge lets us write our own custom operating system logic and safely push performance beyond what others can guess at.
Why Our Tuning Feels Different
Truly Custom
We tune to your parts and your environment (mods, weight, altitude, fuel quality). No recycled "close enough" files.
Reverse Engineers
Professional reverse engineers & software experts. We don't "guess and check" — we know exactly what every table and strategy does.
Safe Power
Clean torque under load, confident towing manners, and power that doesn't have negative long term effects on your truck.