SBT Overlay

Simbox Broadcast Tower

Live the same race

Most iRacing overlays are made for one driver. SBT is made for the whole team.

Download for Windows See how it works

Free beta for Windows. Public release in December.

Two Super Formula cars side by side into a corner, with the SBT timing tower showing positions gained and the relatives panel showing the fight for P12.
Team firstEvery teammate's car, live, on every screen.
Stream outputSeparate from the driver's overlay.
Auto-directedCards that tell the race on their own.
FreeSupported by donations, not paywalls.

One team, one screen

Your whole team, in the same race

Every teammate running SBT shares their car live: fuel, stint, laps and pit stops. The driver, the next driver up, the team manager and the team's stream all live the same race, in real time. It's encrypted with your team key.

  • Stint planner. Book stints in squares and fill in your availability. Teammates without the app use a private web link, even on a phone.
  • The real race on stream. Class standings, rivals' pit stops, driver changes and ongoing battles. Your own strategy stays hidden by default.
  • No blind spots (beta). Teammates can share replays from inside their own car, ready to air on the team's stream.

You drive, SBT directs

A broadcast that tells the race

Your stream gets its own output, separate from the driver's overlay. Cards appear on their own to tell the story: grid show, battles, pit stops, driver changes, replays and the results show.

And for every driver, a clean, light on-screen overlay: tower, relatives, fuel, track map and inputs.

The SBT timing tower with gaps to the class leader, and the relatives panel with the gaps to the cars ahead and behind.

For streamers

Much better, with little effort

Most iRacing streams copy the driver's screen: tiny text, nothing moves, and viewers can't follow the race. SBT gives your stream its own show.

A typical stream

  • The driver's overlays, copied as they are
  • Text too small to read on a phone
  • Nothing happens unless you do it
  • Viewers see one car, not the race

With SBT

  • A stream output built for viewers
  • Large, clean TV-style graphics
  • Cards show up on their own, at the right time
  • Battles, pit stops and the whole team's race

Get started

On air in a few minutes

  1. InstallOne Windows installer. Nothing else to set up.
  2. Join your teamShare one team key with your teammates. Solo works too.
  3. Add it to OBSOne browser source for the stream. SBT does the rest.

Free beta

Download SBT

For Windows 10 and 11, with iRacing. Everything is included in one installer.

Download for Windows
Version
61-m (beta)
Size
16.2 MB
Released
November 6, 2026

The installer is not signed yet, so Windows SmartScreen may warn you. Click More info, then Run anyway.

SHA-256: c65bf78892c35c48722a89331d28f3ea3020becfc020232e33585a11e34b8e90

Questions

Is it really free?

Yes. SBT is free to use. Donations on Buy Me a Coffee and Patreon pay for the team server and for development time.

Does every teammate need SBT?

To share their car live, yes. Teammates without the app can still use the stint planner from a private web link, even on a phone.

Do I need to stream to use it?

No. The driver overlay (tower, relatives, fuel, track map and inputs) works on its own. The stream output is there when you want it.

Will rivals see our strategy?

Not by default. Team data is encrypted with your team key, and your own strategy stays off the stream unless you choose to show it.

Will it slow down my PC?

SBT is built to stay light, inside iRacing and in OBS. The graphics avoid the heavy effects that cost frames in a browser source.

Is it finished?

Not yet: SBT is a free beta, tested every week in real races. The public release is planned for December. Team features are still marked beta in the app. Follow the project on Patreon to hear about new versions first.

Keep it free, keep it running

SBT is free to use. Your support pays for the team server and for development time.

Buy me a coffee Join on Patreon