Double wishbone vs. MacPherson suspension (pros and cons)
When it comes to car suspension systems, double wishbone suspension and MacPherson suspension are two of the most common suspension architectures. Both systems have their pros and cons.
Understanding the pros and cons of each system helps consumers and car enthusiasts make informed decisions when buying a car depending on their use case.
Benefits of double wishbone suspension
1) Improved handling
Double wishbone suspension provides better handling and stability, especially when cornering. Its design allows for a dynamic change in camber in the middle of the corner, maximizing tire-to-road contact. This provides better traction and control, especially on uneven or difficult terrain.
Many double wishbone designs allow the outside rear wheel to point forward upon compression. This allows the car to enter curves sooner. The result is a more agile and responsive vehicle.
2) Adjustable Geometry
Double wishbone suspensions typically have a much wider range of toe adjustment and more options for camber, caster, and toe adjustment. This adjustability allows the suspension geometry to be fine-tuned to specific driving preferences and performance requirements.
Having more control over the vehicle’s alignment is especially beneficial for car enthusiasts who do autocross or take their cars to the race track.
Disadvantages of Double Wishbone Suspension
1) Complexity and Cost
Double wishbone suspensions are more complex and elaborately designed compared to MacPherson struts. Additional components such as upper control arms, upper ball joints, and additional bushings are required, which can increase development time and manufacturing costs.
The complexity of the system can result in additional time and expense for repairs and replacements.
2) Greater weight
The additional components of a double wishbone suspension can contribute to increased weight, resulting in increased unsprung mass. This extra weight can easily affect fuel economy and the overall performance of the vehicle. However, advances in lightweight materials and construction techniques have minimized this drawback in modern designs.
Advantages of MacPherson strut suspension
1) Simple and inexpensive
MacPherson strut suspensions are simpler in design and have fewer parts compared to double wishbone systems. The compact design makes installation and maintenance easier and reduces manufacturing costs. This simplicity allows repairs or replacements to be made faster and more cost-effective.
2) Space Saving
MacPherson struts are space saving and take up less space within the vehicle’s engine bay. This allows for more efficient packing, allowing more room for other components and passengers. This is especially beneficial in vehicles with limited space in the engine compartment.
3) Excellent Balance of Comfort and Handling
MacPherson struts offer a balanced combination of ride comfort and handling. The design provides ample shock absorption and stability, resulting in a smooth, controlled ride.
While the MacPherson strut suspension system may not be able to match the performance of a double wishbone suspension, it offers a good middle ground for daily driving, economy cars, and even some light trucks.
Disadvantages of MacPherson strut suspension
1) Limited adjustability
Unlike double wishbone suspensions, MacPherson struts offer limited adjustment options. This lack of adjustability can limit your ability to fine-tune the suspension characteristics to your specific ride and performance requirements. Enthusiasts looking for a highly customized suspension may find this a limitation. However, aftermarket solutions are often available for enthusiasts who own vehicles with MacPherson struts. For example, camber plates and aftermarket control arms allow additional camber adjustment. Some aftermarket suspension components may also allow additional caster adjustment.
2) Increased Body Roll
MacPherson struts tend to have more body roll when cornering compared to double wishbone suspensions. Due to the networked nature of the system, changes to one wheel can affect the other wheels, reducing overall driving precision and responsiveness.
Cars with double wishbone suspension
Many famous sports cars have double wishbone suspension. Here is a short list of cars known for double wishbone suspension:
1) Mazda MX-5 Miata
The Mazda Miata is considered one of the best affordable sports cars of all time, thanks to its incredible handling. The Mazda Miatas has a custom double wishbone suspension not found on other Mazda models.
2) Tesla
All Teslas use double wishbone suspension. It is much easier to fit a double wishbone suspension to an electric car because it doesn’t have the drivetrain limitations of an internal combustion engine car with a big motor in the front.
Cars with MacPherson strut suspension
1) Porsche 911 (except GT3)
Surprisingly, the Porsche 911 uses MacPherson strut suspension on most models. This is due to packaging limitations, not cost.
2) Subaru WRX STI (and many other sports sedans)
Sports sedans are designed to be fun and fast to drive without sacrificing everyday usability. They are usually front-engine. The Subaru WRX STI is an affordable rally-inspired car with MacPherson strut suspension in the front and double wishbone suspension in the rear.
Conclusion
Double wishbone and MacPherson strut suspensions each have their pros and cons. Which suspension is best for you ultimately depends on your individual application. Consider how you will use your car, your budget and your personal preferences.
Manufacturers carefully evaluate these factors to select the best suspension system for their particular vehicle model, balancing performance, cost and overall customer satisfaction.