Standalone ECUs

Shop by brand

• Holley7 in stock · from $1,449.95The most popular way to run an LS or LT swap: complete Terminator X kits with the harness, wideband and handheld in the box, up to the Dominator for race cars.
• Haltech8 in stock · from $1,695From the Nexus Rebel LS kits to the Nexus R5 vehicle control unit, which replaces the ECU, power distribution and data logger in one box.
• Link ECU8 in stock · from $2,045Wire-in G4X and G5 units, and plug-in ECUs that bolt into the factory harness on the Nissan and Toyota platforms drift and track cars are built on.
• Emtron5 in stock · from $1,700Professional motorsport engine management: the compact SL range and the KV8, KV12 and KV16 for V8s, staged injection and big-power builds.

Want it installed and calibrated? Standalone ECU tuning

Choosing a standalone ECU

Plug-in, wire-in or a kit — which do I need?

A plug-in replaces the factory ECU on a specific car and uses its harness, so nothing is rewired. A kit (Holley Terminator X, Haltech Rebel LS) is an ECU with an engine harness already built for one engine family — the usual way to do an LS or LT swap. A wire-in unit is the ECU alone; it needs a harness built or bought for the car, and suits race cars and unusual combinations. If you are not sure, call — that conversation is free, and a wrong unit is not returnable.

Are these the same prices other dealers charge?

Yes. DEFI is an authorised dealer for Holley, Haltech, Link ECU and Emtron, and every unit here is at the price authorised dealers advertise. Shipping in the continental US is free on top of that.

Do you have them in stock?

Yes — they ship from Corona, CA. Free in the continental US; Alaska and Hawaii are quoted by phone. You can also collect from the shop.

Can you install and tune it?

Yes. We install, wire and calibrate standalone engine management and tune it on our Mainline ProHub hub dyno, with the full sheet at the end. Shop labor is $265 an hour, quoted against your car.

Are standalone ECUs street legal?

No. None of these carries a CARB Executive Order. They are competition engine management: not legal on a pollution-controlled vehicle in California, and a car running one will not pass a smog inspection.

Can I return one?

No. There are no returns or exchanges on third-party hardware once it ships — the manufacturer’s warranty is the warranty. Ask us about fitment before you order.