iRacing Wheel LFE Explained: What Each Effect Does and How to Tune It

Wheel LFE is iRacing's system for playing its low frequency effects, the tactile cues normally sent to a bass shaker, through the wheelbase motor itself. It runs in parallel with ordinary force feedback rather than replacing it, which is why a wheel can suddenly carry detail it never carried before.

It is not something anyone has to buy. Wheel LFE and the 360 Hz mode run on every wheelbase MOZA makes, the entry-level MOZA R3 and the flagship R25 Ultra alike, and both arrive with a software update rather than a new purchase.

Where Wheel LFE came from

The acronym stands for low frequency effects. In sim racing it has meant something specific for years: a low frequency signal synthesised from the sim's own physics and sent to a bass shaker, the tactile transducer bolted to a seat or rig frame, translating slip and impacts into something felt through the body rather than through the controls.

Wheel LFE builds that same family of effects from the car physics and plays them through the wheelbase motor instead, so the rim takes the shaker's place.

Reproducing it asks for a motor that can add small, fast modulations on top of the steering torque it is already holding. How cleanly those modulations read depends on how smooth that motor is underneath them, which is where the very low cogging design of a base like the MOZA R16 Ultra helps.

The controls sit in iRacing under Options, in the Misc tab, where the effect is switched on, given its overall level, and told to build its vibrations from the physics rather than from game audio. Turning it on is a question of software versions rather than model: MOZA's Pit House needs to be on 1.3.1.50 or later and the base on firmware 1.2.5.5 or later, after which both this effect system and the 360 Hz mode arrived together, with iRacing's 2025 Season 3 build.

LFE is not force feedback, it is a sensation layer

Normal force feedback is a computation of the forces acting on the steering system: the self-aligning torque, the trail geometry that generates it, and the load state at the front axle. When the front tyres start to slide, the aligning torque falls away and the wheel goes light. That is the state of the steering itself, arriving through the channel the hands already read.

LFE carries something else. Its channels are driven by engine speed, slip ratio, surface type and chassis acceleration. In a real car those cues reach the driver mostly through the seat, the pedals and the floorpan, far more than up the steering column, which receives only a heavily filtered fraction of that energy.

So the two streams answer different questions. Force feedback reports what the steering is doing, LFE reports what the rest of the car is doing, and playing the second one through the rim works because it puts the information where the driver is already paying attention. It also creates the problem that governs all of the tuning below: both streams share one actuator. Whatever the steering is already drawing from the motor, the LFE layer has to fit into what is left. The base's torque ceiling is therefore the ceiling for both signals at once, and on a flagship like the MOZA R25 Ultra that is 25 Nm.

What the seven effects carry

Seven channels make up the system, and the sim does not ship them at the same level. The balance it chooses is an editorial judgement about which of them carry information a driver can act on.

• Wheel slip is pushed hardest. It reports a tyre passing its limit in a different modality from the fading aligning torque, which makes it most valuable at the rear axle, where the steering column only reports late and indirectly.

• Gear change is raised as well, a discrete thump on each upshift and downshift.

• Car body acceleration sits at the authored baseline, carrying chassis load changes, impacts and heavy kerb strikes.

• Rev limit also sits at baseline, a sharp pulse when the engine hits the limiter.

• Rumble strip is pulled down slightly, since kerbs arrive hard enough to register without much help.

• Engine RPM is cut hard. It runs continuously with engine speed, which the driver can already see on the dash and hear through the exhaust.

• Road texture is cut hardest of all, a continuous grain from the surface under the tyres.

Gear change and rev limit are the situational pair. Both are short, and both confirm that something happened without competing for attention the rest of the lap.

Who gets the most from Wheel LFE

The clearest case is a rig with no bass shaker. Without one, this class of information has no dedicated route to the driver at all, reaching them only as far as it disturbs the steering. Wheel LFE gives it one.

Drivers who cannot rely on the sim's audio cues gain the most obvious benefit, since the information arrives through touch instead of sound. The same reasoning covers anyone racing late at night with the volume down, or on a busy grid where engine notes are buried under traffic.

Beyond that, the value concentrates wherever the steering is quietest. A rear tyre stepping out is the clearest case, and how much kerb the car has actually taken is the next. The slip and kerb channels carry both, ABS included, since ABS cycles brake pressure to control exactly the slip that channel reports. That is why those two are the ones most drivers end up keeping.

How to balance the effects

At its shipped level the layer is deliberately loud, which is the usual reason a MOZA wheelbase starts buzzing or sounding mechanical after an update. Nothing is faulty. The effects are simply new, and at full level.

A continuous engine vibration does not simply add noise next to the wheel slip cue. It masks it. Both arrive at the same place, as vibration in the rim, so a constant engine buzz raises the floor against which a sudden, transient slip has to be noticed. Attenuating the continuous channel therefore improves the contrast of the one that matters, and the sim's own default balance is consistent with that logic.

The values are gains in decibels, not a zero to one hundred slider. Zero is the authored baseline, negative attenuates, positive boosts, and because the scale is logarithmic a change of roughly 6 dB halves or doubles the amplitude. Small numbers move more than they look like they should.

Overall loudness is adjustable from the settings screen. The per-effect gains live in the app.ini file inside the iRacing folder under Documents, grouped in a section labelled [TrueForce], each one a line ending in _dB. Reading them there is the reliable way to see where an install actually sits, since the shipped balance has changed between builds. Close the sim before editing, keep a copy of the file first, and relaunch to feel the change.

The method that follows is subtractive. Pull the atmospheric channels down first, so the rim stays quiet until something actually happens, then set the event and grip channels to sit just above that new floor, where they read cleanly rather than loudly. Change one channel at a time, on a car and circuit familiar enough to notice the difference, and check across classes before settling. A stiff formula car and a softly sprung road car generate very different vibration content, which is also why chasing somebody else's numbers seldom transfers.

Wheel LFE compared with a bass shaker

The two are not alternatives and both can run at once. A shaker puts its energy through the whole body, which is anatomically where a real car sends chassis information. It is not the only way to occupy that channel, since a haptic motion system such as the MOZA HMA150 delivers wide-band vibration from 0 to 200 Hz and moves the rig as well. The wheel works differently, delivering the same class of events as torque through the rim, so its advantage is placement rather than power. Where a rig has both sides covered, a division of labour beats duplication: the seat carries the ambience and the heavy low end, the wheel keeps a tight subset of grip and boundary cues.

Wheel LFE is not the 360 Hz mode

These two are constantly conflated, but they solve different problems. Wheel LFE adds a layer of sensation. The 360 Hz mode changes how the ordinary steering torque signal is delivered.

The physics engine calculates at 360 Hz. Force feedback output to the wheel has historically been sampled at 60 Hz, one torque value per cycle. The 360 Hz mode does not change that 60 Hz cycle. Each update now carries the current torque value plus the previous five real calculated samples, sent as one package, which the wheelbase then replays in order.

Three things follow, and all three are commonly misunderstood. It does not raise the update rate, it raises the data density per cycle. It does not interpolate or invent detail, because all six samples are values the physics already produced. And it is not free, since spreading that batch across the frame window means roughly 16.7 milliseconds of playback delay rather than firing everything instantly.

Turning the 360 Hz mode on or off does not change the content of the Wheel LFE signal. They are configured separately and act on different data. The switches for the two features sit in app.ini under a section called Force Feedback, separate from the effect gains: loadMozaAPI enables the MOZA integration that carries both, and enableFFB360HzInterpolated governs the batched delivery on its own. Both default to 1.

Conclusion: Feeling the Rest of the Car

Ordinary force feedback tells a driver what the steering is doing. Wheel LFE tells them what the rest of the car is doing: a rear tyre letting go, a kerb taken deeper than intended, a shift that did or did not engage. The settings decide how much of that reaches the hands, and the balance that suits one car and one driver will not be the same as the next.