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RX-8 ECU tune
Your RX-8
Pick your year so we only show parts that fit your car.
Why do it
The best bolt-on power gain on the RX-8. Cobb discontinued its RX-8 Accessport years ago, so today most owners use VersaTuner, which supports both Series I (2004–2008) and Series II (2009–2011) cars, or a rotary specialist tuner.
Heads up
A bad tune can damage a rotary. Use a well-known rotary tuner, not a generic one.
Tools you'll need
- Tuning device or laptop setup from your tuner
- Battery charger to keep voltage steady
Parts to buy
- VersaTuner for the RX-8 Supports Series I and Series II RX-8s, with ready-made tunes and custom tuning.Fits 2004–2011⚠ Buy the Series 1 (2004–2008) version.⚠ Buy the Series 2 (2009–2011) version.
Doesn't fit your car (0)
Always double-check fitment for your exact year, trim and transmission before buying. Prices change. ModBuddy doesn't earn money from these links.
Official guides & videos
Before you start
- Cobb's RX-8 Accessport is discontinued. Most owners now use VersaTuner (supports 2004–2008 Series I and 2009–2011 Series II) or a rotary specialist tuner.
- Know exactly what parts are on your car (intake, exhaust, cat) and what octane you run. The tune has to match.
- Get a compression test first if you don't know your engine's health. A tune won't fix a tired rotary.
Video guide
This is the tuner company's own video, so it matches the software exactly. Each ▶ button below jumps to that step in the video.
Watch the whole videoSteps
Set up the software
- Install the tuning software on a laptop and get the interface cable and license for your car, following VersaTune's instructions.
Keep the voltage steady
- Connect a battery charger or maintainer. A voltage drop in the middle of a flash can leave the ECU unable to start the car.
Connect and save your stock file
- Plug the cable into the OBD-II port under the dash and turn the ignition on (engine off).
- Read and save the stock ECU file somewhere safe before changing anything. That's your undo button.
Pick the right tune
- Choose a tune that matches your exact parts and octane, or one made for you by a rotary tuner.
- Don't load a tune made for parts you don't have.
Flash it
- Start the flash and don't touch anything until it says it's finished. Don't open doors or turn on accessories during the flash.
Drive gently and log
- Start the car, let it warm up fully, and drive gently at first.
- Record data logs and have your tuner review them before doing hard pulls.
How to know it worked
- Starts and idles normally.
- No check-engine light.
- Your tuner has reviewed your logs and confirmed safe numbers.
Safety first
- Park on flat, solid ground, set the parking brake and chock the wheels.
- Use jack stands rated for your car. Never get under a car held up only by a jack.
- Let the engine and exhaust cool completely before touching them.
- Disconnect the negative battery terminal before unplugging sensors or electrical parts.
- Wear safety glasses, and gloves around sharp heat shields and hot fluids.
- Tighten bolts to the torque spec in your factory service manual.
- If a step doesn't match your car or you're unsure, stop and ask a shop.
These are overview steps written to help you plan the job. Always follow the instructions that come with your part and the procedures and torque specs in your factory service manual. Horsepower is an estimate; results vary.