Classic Subaru tuning software

Edit, flash, log, and live-tune your Subaru.

PulseWidth is a Windows tuning suite built for the classic Subarus: a full ROM editor, flashing with real pre-flight checks, live data and diagnostics, and a tune history that follows each car. 2001-2006 WRX, STi, Forester Turbo, Legacy B4, and Outback H6.

Early Access

Core flashing, diagnostics, cloud workflows, and account systems are live now. Coverage keeps deepening across the 2001-2006 classic Subaru fleet, and the app always shows exactly what is supported before you commit.

Explore Features View Pricing Login

WRXSTiForester TurboLegacy B4Outback H6

PulseWidth ROM editor with a 2003 USDM WRX calibration open: table tree with boost control, fuel system, and ignition timing categories — The actual app. A 2003 USDM WRX calibration open in the ROM editor.

134

Classic calibrations

Individually mapped 2001-2006 Subaru calibrations, embedded in the app.

Model families

WRX, STi, Forester Turbo, Legacy/Liberty B4, and Outback H6.

200+

Log channels

Live data, datalog analysis, and full-screen digital dashboards.

Soldering required

Read, flash, log, and diagnose through the factory OBD-II port.

Know before you flash

Load your ROM or plug in the car and PulseWidth identifies the exact calibration, then tells you what is supported and what is still early access. No guessing, no forum archaeology.

Flash with a net

Every write goes through pre-flight checks: ROM size, processor match, checksums, battery voltage, and a stock backup prompt. Test writes and read-back verify are one click away.

See what the engine sees

Live sensors, knock feedback, datalog analysis, DTC read and clear, and full-screen dashboards, with every log and revision tied to the car it came from.

Flagship platform / 2001-2006

The 02-05 WRX era is our flagship, not an afterthought.

134 calibrations mapped across the GD WRX and STi, Forester Turbo, Legacy B4, and Outback H6. Flash through the stock OBD-II port, log the real channels, and live-tune supported cals while the engine runs.

Explore the classic Subaru platform

PulseWidth digital dashboard in the 2003 WRX tune theme showing boost, AFR, knock, and wastegate duty

Built in-house

Definitions mapped by hand, tested on real ECUs.

Every one of the 134 classic Subaru calibrations we support ships inside the app, built against real ROM dumps and checked on the bench before it reaches your car. One platform at a time, done properly.

Read more about how we work on the about page.

Rolling release

Shipping updates, not launch promises.

PulseWidth updates land continuously. Coverage that is still maturing is labeled early access in the app, so you always know the difference between proven and new. Public release notes begin at launch.

Follow along on the releases page.