Wheelbase & FFB Notes: Fanatec/Moza API Updates + Logitech G27 Tweak

Small Changes, Big Feel The 2025 Season 4 build tucked in several force feedback (FFB) updates that directly affect how your wheelbase communicates road feel and how responsive your hardware stays in long sessions. They’re easy to miss in the patch notes, but if you run Fanatec, Moza, or older Logitech hardware, you’ll want to…

Small Changes, Big Feel

The 2025 Season 4 build tucked in several force feedback (FFB) updates that directly affect how your wheelbase communicates road feel and how responsive your hardware stays in long sessions. They’re easy to miss in the patch notes, but if you run Fanatec, Moza, or older Logitech hardware, you’ll want to know what changed.

Fanatec: TrueForce Gain Control

iRacing has added a new app.ini variable for Fanatec users:

[TrueForce]  
trueForceSetGain= 1
  • By default, iRacing will set TrueForce gain to 100% when the sim launches.
  • Setting trueForceSetGain=0 disables this behavior, leaving gain control entirely in your hands.
  • Why it matters: if you prefer to fine-tune TrueForce through the Fanatec wheel tuning menu instead of in-sim hotkeys, this new toggle keeps iRacing from overwriting your adjustments.

This gives advanced users more consistency across sessions and avoids surprises when swapping profiles.

Moza: Responsiveness Fix

The Moza API has been updated to resolve an issue where the wheel could become unresponsive after extended running.

  • This bug fix improves reliability in endurance events where long stints or driver swaps could previously leave the base locked.
  • You shouldn’t need to change anything—just update and race knowing your Moza gear is less likely to drop out mid-session.

Logitech: Softer G27 Rumble Strips

For Logitech G27 owners, the patch softened the rumble strip profile in the 360Hz FFB channel:

  • Old behavior: exaggerated “machine gun” chatter when hitting curbs, sometimes louder than it should be.
  • New behavior: smoothed profile to better replicate real-world curb vibrations, with less audible noise and a more natural feel through the rim.

It’s a subtle quality-of-life tweak, but a welcome one for anyone still running this classic wheel.

Why It Matters

While none of these changes overhaul iRacing’s FFB system, they address pain points for three distinct user groups:

  • Fanatec: more control over TrueForce tuning.
  • Moza: greater hardware stability and confidence in long races.
  • Logitech G27: cleaner, less harsh curb feedback.

Together, they make Season 4 a little smoother for drivers across the wheelbase spectrum.

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