When it comes to optimizing your vehicle’s suspension, especially for performance applications, understanding the nuances of damper and spring technology is crucial. Long stroke dampers, like the Xida, are designed to offer an extended range of motion, but to fully utilize this capability, they often require a dual spring setup incorporating helper springs. This article delves into why helper springs are essential for maximizing the performance of long stroke damper systems, focusing on key aspects such as suspension articulation, weight considerations, progressive spring rates, and cost implications.
The Critical Role of Helper Springs in Suspension Articulation
In a car suspension system, spring stroke and suspension articulation are intrinsically linked. Consider a vehicle weighing 2000 lbs with a motion ratio just under 1.5:1. A short 700 lb spring in this setup won’t compress sufficiently to allow for meaningful droop travel when paired with a long stroke damper. To achieve the correct ride height, adjustments are often made by lowering the preload collar, which can result in 25-60mm of free play in the springs. This is where helper springs become indispensable.
Without secondary, or helper springs, the main spring can lose contact with its perch during suspension droop. Essentially, there isn’t enough spring stroke left to push the tire downwards and maintain consistent contact with the road surface, especially over uneven terrain or during aggressive cornering. Helper springs address this issue by maintaining pressure and ensuring the main spring remains seated, even when the suspension extends.
Weight and Spring Rate Efficiency
Achieving the ideal spring rate for competitive driving and high-performance use while maintaining adequate spring stroke can pose a challenge. Using a single, longer spring (9-11 inches) to compensate for stroke might seem like a solution, but springs, particularly more budget-friendly options, are not lightweight. This approach adds unnecessary weight to the suspension, which is detrimental to overall vehicle dynamics.
Manufacturers like Hyperco and Swift are known for producing some of the lightest and most consistently rated springs available. We often utilize Hyperco springs, as they offer comparable performance to Swift but often at a similar price point. Many Hyperco springs also incorporate their OBD (Optimum Body Diameter) technology, which further reduces weight and enhances spring stability under compression, contributing to more precise and responsive handling.
Progressive Rate Springs and Performance Enhancement
Beyond the issue of weight, the spring rate requirements of a suspension system change throughout its range of motion. For instance, a Miata doesn’t need extremely high spring rates (400-800 lbs) when the suspension is fully extended, as the load on the contact patch is minimal in this state. In such situations, a lower spring rate is actually more beneficial, allowing the tire to better conform to minor road imperfections and maintain grip.
This is where the concept of progressive rate springs comes into play. A progressive rate is achieved effectively with a dual spring setup. By using a helper spring with a very low rate in conjunction with a main spring, the suspension effectively has a lower initial spring rate at extension, transitioning to the higher rate of the main spring as it compresses. This is why purpose-built race cars with significant damper stroke (over 75mm) almost universally employ dual spring systems. Off-road and rally vehicles often take this concept even further, sometimes utilizing three or more stacked springs to achieve an even wider range of spring rates.
Cost Considerations and Performance Trade-offs
While the benefits of dual spring systems with helper springs are clear, there are cost implications to consider. If you initially opt for a single spring setup and later decide to upgrade to dual springs, it may be necessary to replace the main springs with a shorter set. This spring swap can add approximately $150 per pair to the overall cost.
Recognizing these budgetary constraints, we offer the Xida Club Sport coilovers in configurations both with and without helper springs for Miata owners. While the system undeniably performs optimally with dual springs, we understand that cost can be a deciding factor. During testing of the single spring Club Sport setup on a bumpy local road course using a Spec Miata with 9″ wheels, the performance was notably good. In fact, it was sufficiently impressive to confidently offer the XCS without helpers as a viable option. It’s worth remembering that many enthusiasts have successfully used high spring rate Ground Control and other coilover sleeves with Bilstein and Koni Sport dampers for years with positive outcomes.
However, it’s important to acknowledge that a single spring setup is a compromise. While functional and offering improvements over stock suspension, it is inherently “less than optimum” compared to a dual spring system designed from the outset for peak performance. And “less than optimum” was simply not part of the design philosophy behind the Xida coilovers.
In conclusion, while helper springs might represent an additional upfront cost, they are a critical component for unlocking the full potential of long stroke damper suspension systems. They ensure consistent tire contact, optimize spring rate progression, and ultimately contribute to superior handling and performance. For those seeking the best possible suspension performance, particularly with long stroke dampers like the Xida, investing in helper springs is a worthwhile upgrade.
