What is track width (TW)?

Understanding Track Width

Definition and Measurement

Track width is defined as the distance between the centerlines of the left and right tires on the same axle. It is typically measured in millimeters or inches and can vary between the front and rear axles of a vehicle. The track width measurement is taken from the ground up to the center of the tire, perpendicular to the vehicle’s longitudinal axis.

Front and Rear Track Width

Most vehicles have different track widths for the front and rear axles. This difference is due to various factors such as suspension design, weight distribution, and the intended purpose of the vehicle. For example, a front-wheel-drive car may have a wider front track width compared to the rear to improve steering response and stability during cornering.

Vehicle Type	Front Track Width (mm)	Rear Track Width (mm)
Sedan	1,550 – 1,650	1,540 – 1,640
SUV	1,600 – 1,700	1,590 – 1,690
Sports Car	1,650 – 1,750	1,600 – 1,700

Table 1: Typical track width ranges for different vehicle types.

Factors Affecting Track Width

Several factors influence the track width of a vehicle. These factors are carefully considered by automotive engineers when designing a vehicle to ensure optimal performance, stability, and safety.

Suspension Design

The suspension design plays a crucial role in determining the track width of a vehicle. The type of suspension used, such as MacPherson strut, double wishbone, or multi-link, dictates the placement of the wheels and the overall track width. Engineers must balance the suspension geometry to achieve the desired handling characteristics while maintaining a suitable track width.

Wheel and Tire Size

The size of the wheels and tires also affects the track width. Larger wheels and wider tires generally result in an increased track width, as the centerline of the tire moves outward. This is one of the reasons why high-performance vehicles often feature wider wheels and tires compared to their standard counterparts.

Vehicle Purpose and Design

The intended purpose and design of a vehicle heavily influence its track width. Sports cars and racing vehicles often have wider track widths to enhance stability and cornering performance. On the other hand, passenger cars and SUVs may have narrower track widths to optimize interior space and improve overall efficiency.

Impact of Track Width on Vehicle Dynamics

Track width has a significant impact on various aspects of vehicle dynamics. Let’s explore how track width affects stability, handling, and performance.

Stability

A wider track width generally improves a vehicle’s stability by lowering its center of gravity and increasing its resistance to rollover. With a wider stance, the vehicle has a more balanced weight distribution, which enhances its ability to maintain traction and stability during cornering and high-speed maneuvers.

Handling

Track width plays a vital role in a vehicle’s handling characteristics. A wider track width typically results in better cornering performance, as it allows for more lateral force to be generated by the tires. This increased lateral force enables the vehicle to maintain higher cornering speeds and exhibit better overall handling.

However, it’s essential to note that an excessively wide track width can negatively impact handling in certain situations. For example, a vehicle with an extremely wide track width may experience increased tire scrub during tight turns, leading to reduced maneuverability in urban environments.

Performance

The relationship between track width and performance is closely tied to the vehicle’s stability and handling characteristics. A wider track width can contribute to improved acceleration, braking, and cornering performance by providing a more stable platform for the vehicle to operate on.

In motorsports, track width is often optimized to suit the specific requirements of the racing series and the track conditions. Racing teams may adjust the track width to find the perfect balance between speed, stability, and tire wear.

Advantages and Disadvantages of Wider Track Width

While a wider track width offers several benefits, it also comes with some drawbacks. Let’s examine the advantages and disadvantages of having a wider track width.

Advantages

1. Enhanced stability: A wider track width lowers the center of gravity and improves the vehicle’s resistance to rollover, resulting in better overall stability.

2. Improved handling: With a wider stance, the vehicle can generate more lateral force, enabling better cornering performance and handling characteristics.

3. Increased tire contact patch: A wider track width allows for a larger tire contact patch, which improves traction and grip, especially during cornering and braking.

4. Better weight distribution: A wider track width can contribute to a more balanced weight distribution, enhancing the vehicle’s overall performance and stability.

Disadvantages

1. Increased tire wear: A wider track width can lead to increased tire wear, particularly on the outer edges of the tires, due to the higher lateral forces experienced during cornering.

2. Reduced maneuverability: Vehicles with extremely wide track widths may face challenges in tight urban environments, as the increased width can hinder maneuverability and make navigating narrow spaces more difficult.

3. Increased aerodynamic drag: Wider track widths can result in increased aerodynamic drag, which may negatively impact fuel efficiency and top speed.

4. Higher manufacturing costs: Designing and manufacturing vehicles with wider track widths may incur higher costs due to the need for specialized suspension components and larger wheel wells.

Frequently Asked Questions (FAQ)

1. Q: How does track width differ from wheelbase?
   A: Track width refers to the distance between the centerlines of the left and right tires on the same axle, while wheelbase is the distance between the front and rear axles of a vehicle.

2. Q: Can track width be adjusted on a vehicle?
   A: In most cases, track width cannot be easily adjusted on a production vehicle without significant modifications to the suspension and wheel components. However, in motorsports, teams may make adjustments to the track width to optimize performance for specific track conditions.

3. Q: Does track width affect tire wear?
   A: Yes, a wider track width can lead to increased tire wear, particularly on the outer edges of the tires. This is due to the higher lateral forces experienced during cornering, which puts more stress on the tires.

4. Q: Why do sports cars typically have wider track widths?
   A: Sports cars often feature wider track widths to enhance stability, handling, and cornering performance. The wider stance allows for better weight distribution and increased lateral force generation, enabling the vehicle to maintain higher speeds through turns.

5. Q: Can a wider track width negatively impact a vehicle’s performance?
   A: In some cases, an excessively wide track width can negatively impact a vehicle’s performance. It may lead to increased tire scrub during tight turns, reducing maneuverability in urban environments. Additionally, a wider track width can result in increased aerodynamic drag, which may affect fuel efficiency and top speed.

Conclusion

Track width is a fundamental measurement in the automotive industry that significantly influences a vehicle’s stability, handling, and overall performance. By understanding the factors that affect track width and its impact on vehicle dynamics, automotive engineers can design vehicles that strike the perfect balance between stability, handling, and efficiency.

While a wider track width offers several advantages, such as enhanced stability and improved cornering performance, it also comes with some drawbacks, including increased tire wear and reduced maneuverability in certain situations. Ultimately, the optimal track width for a vehicle depends on its intended purpose, design goals, and the specific requirements of the intended operating environment.

As the automotive industry continues to evolve, with advancements in suspension technology and the growing popularity of electric vehicles, the importance of track width in vehicle design remains paramount. By carefully considering and optimizing track width, manufacturers can create vehicles that deliver exceptional performance, safety, and driving enjoyment to customers worldwide.