In a mechanic simulator, ET stands for Einpresstiefe, a German term that translates to offset. It is a critical measurement when dealing with wheels and their fitment on a vehicle.
Understanding Wheel Offset (ET)
Wheel offset, or ET, defines the distance from the wheel's hub mounting surface (the part that bolts to the vehicle) to the true centerline of the wheel. This measurement significantly impacts how a wheel sits within the wheel well and its interaction with suspension components and the vehicle's handling characteristics.
The Technical Definition of ET (Offset)
The ET value represents the precise distance between the wheel bearing and the wheel's attachment position on the vehicle. This measurement is crucial because vehicle and wheel manufacturers aim to minimize wear on components. To achieve this, the wheel must be centered as effectively as possible over the wheel bearing, and the ET value helps ensure this alignment.
There are three main types of offset:
| Offset Type | Description | Impact on Wheel Position |
|---|---|---|
| Positive ET | The hub mounting surface is positioned towards the front (outboard side) of the wheel's true centerline. Most modern cars use positive offset. | The wheel sits further inward into the fender well. |
| Negative ET | The hub mounting surface is positioned towards the rear (inboard side) of the wheel's true centerline. Common on older vehicles or deep-dish wheels. | The wheel sits further outward, protruding from the fender well. |
| Zero ET | The hub mounting surface is perfectly aligned with the wheel's true centerline. | The wheel is equally balanced, with half of its width sitting inward and half sitting outward from the mounting point. |
Why is ET Important in Mechanic Simulators?
Understanding and correctly adjusting ET is vital in mechanic simulator games for several reasons, reflecting real-world automotive principles:
- Vehicle Handling: Incorrect offset can alter the scrub radius, affecting steering feel, stability, and control, especially during cornering.
- Tire Wear: An improper ET can lead to uneven tire wear, reducing tire lifespan and performance.
- Clearance: The offset determines whether the wheel and tire assembly will clear suspension components, brake calipers, or fender lips. Using the wrong ET can cause rubbing or prevent the wheel from fitting at all.
- Aesthetics: For many players, adjusting ET is also about achieving a desired stance or visual appeal for their custom vehicles.
- Performance Tuning: Changing the offset can subtly alter track width, which can be a tuning parameter for specific racing setups within the game.
Adjusting ET in Game
In mechanic simulator games, players often encounter ET when selecting new wheels or modifying existing ones. The game will typically display the ET value, allowing players to choose wheels that fit correctly or to experiment with different offsets to achieve specific performance or aesthetic goals. This might involve purchasing wheels with predetermined offsets or, in more advanced simulators, using spacers or specific hub components to fine-tune the ET.
