Le Mans Ultimate (LMU) – RaceLab Overlays & Telemetry

1. LMU basic setup for RaceLab

Before you add overlays or layouts, make sure LMU is sending data correctly to RaceLab. Menu names and options may change as LMU updates, so always double-check the latest information in the RaceLab Garage and the official LMU documentation. [1]

1. Update LMU and RaceLab
   Install the latest LMU build and make sure RaceLab is on the current stable or beta version. Restart your PC after any major update.
2. Launch RaceLab first
   Start RaceLab before LMU so the telemetry listener and overlays are ready to receive data.
3. Check the LMU integration card in RaceLab Garage
   Open the Garage inside RaceLab and look for the LMU card. Follow the instructions there for the current port or plugin or network settings. [2]
4. Enable LMU telemetry or data output
   In LMU’s options, enable the telemetry or data output feature recommended by RaceLab for example, a plugin or UDP setting. Save and restart LMU after changing these options.
5. Verify data is received
   Join a test session, then check the RaceLab status bar and overlays. Lap times, speed and position should update as soon as you leave the pits.

If LMU is under scheduled maintenance, you can still prepare the RaceLab side first, then confirm data flow once the servers reopen.

2. Using overlays & layouts in LMU

RaceLab supports both standard overlays and full-screen layouts with LMU. In most cases, layouts are more stable and flexible, especially for streaming and multi-monitor setups.

2.1 Standard overlays

• Use overlays such as Relative, Standings, Radar and Fuel as separate browser windows.
• Position them in LMU using either Windowed or Borderless window mode to avoid taskbar and focus issues. [3]
• Keep overlays away from the Windows taskbar edge to reduce flicker and hiding behaviour when LMU loses focus.

2.2 Layouts (recommended)

• Create a custom LMU layout inside RaceLab that matches your screen or stream resolution single screen, triples or ultrawide.
• Place widgets for Relative, Standings, Radar, Fuel and any extra panels you want.
• Use a single browser source in OBS or a single window on your monitor instead of many individual overlay windows – this is usually more stable.
• Save your layout profile and back it up so you can quickly restore it after LMU or RaceLab updates.

3. LMU with VR & triple screens

LMU supports triples and VR, and RaceLab can work with both – but there are some important points to remember:

• VR in RaceLab requires a Pro subscription. VR is a Pro-only feature and is not available on the free tier. [4]
• Configure your triple-screen geometry bezel, field of view, angles in LMU before adding overlays or layouts.
• Once triples look correct in-game, then position your RaceLab layout so it lines up with the centre or side screens the way you like.
• For VR, keep overlays minimal and high-contrast to avoid clutter and motion sickness. Test in a private session before joining online races.

If you change LMU resolution or screen mode, you may need to adjust your RaceLab layout positions to match the new window size.

4. Performance & FPS tips

LMU is demanding on both CPU and GPU. Overlays themselves are usually light, but browser windows and capture methods can add extra load if not configured carefully.

• Prefer borderless window or a mode recommended by the LMU team for best stability with overlays.
• Close unused overlay windows or browser tabs – each extra overlay consumes resources.
• If streaming, test both game capture and browser source in OBS to see which performs better on your system.
• Lower heavy graphics options in LMU such as shadows, reflections and crowds before reducing important clarity settings such as resolution and anti-aliasing.
• Watch your CPU and GPU usage in a monitoring tool so you know whether LMU, RaceLab or OBS is the bottleneck.

5. Troubleshooting & common issues

5.1 No data in overlays

• Check that LMU is not in offline maintenance mode – online services may be down.
• Verify that telemetry or data output is enabled in LMU and matches the port or plugin settings shown in the RaceLab LMU integration card. [2]
• Confirm that your firewall or antivirus is not blocking LMU or RaceLab.
• Restart LMU and RaceLab, then try a simple test session such as practice or time trial.

5.2 Overlays not visible or flickering

• Make sure LMU is running in a supported window mode, often Borderless window.
• Avoid placing overlays directly on top of the Windows taskbar or system tray area.
• If using multiple monitors, confirm that the overlays are opened on the correct screen and not hidden behind the game window.

5.3 VR or triples look misaligned

• Re-run LMU’s triple-screen or VR calibration tools first.
• Then adjust your RaceLab layout positions to match the new resolution or projection.
• If the view breaks after a resolution change, try restarting LMU and RaceLab once the new settings are saved.

6. Sources & references

1. Official Le Mans Ultimate game information and patch notes. ↩ back
2. RaceLab Garage integration card for LMU, showing current connection and telemetry setup details. ↩ back
3. RaceLab Garage and community guidance on using overlays in windowed or borderless modes. ↩ back
4. RaceLab Pro feature list, including VR support requirements. ↩ back