Grip Guide: Understanding Coilovers for Your Subaru
Welcome to the first installment of our "Grip Guide" series at GripWorx Suspension, where we’ll be diving deep into all things suspension-related, particularly for Subaru vehicles. This week, we’re focusing on coilovers—what they are, how they work, and why they’re crucial for anyone looking to enhance their Subaru’s performance on the road or track.
What Are Coilovers?
At their core, coilovers are a type of suspension that combines a shock absorber and a coil spring into one assembly. Unlike stock suspension, which often offers limited adjustment, coilovers allow you to make precise adjustments to various factors, including ride height, damping, and spring rate.
With high-quality coilovers, you can:
- Adjust your ride height: Lower your Subaru for a more aggressive stance or raise it slightly for more ground clearance in specific conditions (especially useful if you’re balancing track days with daily driving).
- Control damping: Damping adjustments let you fine-tune how stiff or soft your suspension is, impacting how your Subaru reacts to bumps and imperfections on the road or track.
- Tweak spring rates: A key factor in suspension tuning, spring rates affect how much your car compresses under load. A higher spring rate means less body roll, which is great for autocross and track driving, but may reduce comfort on bumpy roads.
Understanding Damping: Digressive vs. Linear
Before we dive into specific coilovers, it’s important to understand the difference between digressive and linear damping, as it plays a key role in how your suspension behaves.
- Linear Damping provides a predictable, consistent resistance as the suspension compresses or rebounds. This setup is ideal for those looking for a smooth, consistent ride, making it better suited for street applications where comfort is a priority.
- Digressive Damping, on the other hand, is more performance-oriented. It offers more resistance at slower suspension speeds (like cornering) and less resistance at higher speeds (like hitting bumps), giving you more control during aggressive maneuvers without sacrificing ride quality over rough roads. This characteristic makes digressive damping highly desirable for track use, where quick response and controlled body roll are critical.
The Unique Technology of Öhlins DFV
Öhlins is renowned for its innovative Dual Flow Valve (DFV) technology, which sets its suspension systems apart from traditional designs. The DFV enables improved damping performance by allowing for separate control of low-speed and high-speed damping. This means your suspension can provide a smooth ride over minor bumps while maintaining control and responsiveness during aggressive cornering. By utilizing this technology, Öhlins gives you the best of both worlds: comfort for everyday driving and performance for high-speed track days.
Adjustability of Coilovers
One of the key benefits of coilovers is their adjustability. Here's a breakdown of the various adjustable features:
- Damping Adjustment: Coilovers can be equipped with one-way, two-way, or three-way adjustable damping settings.
- One-Way Adjustable typically adjusts rebound damping only but can affect compression slightly, making it a good option for those who want basic adjustability.
- Two-Way Adjustable allows for separate adjustments for both compression and rebound, giving you greater flexibility to fine-tune your setup based on driving conditions.
- Three-Way Adjustable takes this a step further, offering independent adjustment of high-speed and low-speed compression, along with rebound, allowing for the most precise tuning available.
- Camber Adjustable Top Hats: These are crucial for fine-tuning your wheel alignment, particularly for track use, where optimal handling is essential.
- Adjustable Length Shock Bodies: The length of the shock body can affect ride height independently of spring compression, allowing you to dial in your setup without compromising suspension travel.
Exploring BC Racing Coilover Series
BC Racing offers a range of coilover series designed to meet various performance needs:
- BR Series: A solid choice for street and light track use, featuring linear valving and adjustable height. This series is popular among everyday enthusiasts seeking a balance between comfort and performance.
- DS Series: Known for its digressive damping, this series provides a balance between comfort and performance, making it suitable for both daily driving and track use.
- ER Series: This series features 30-click adjustable compression and rebound settings, along with remote reservoirs for improved heat dissipation. It's ideal for those looking to take their setup to the next level.
- HM Series: The BC Racing HM Series Coilover System combines features from both the RM Series and the ER Series. It utilizes an inverted mono-tube damper for improved performance and durability, similar to the RM Series, while also offering independent compression and rebound adjustments like the ER Series.
- RM Series: Aimed at motorsport enthusiasts, this series offers additional adjustments for a more customized setup, enhancing performance on the track.
- ZR Series: The top-tier option, offering extensive adjustability with 15-click low-speed and 12-click high-speed compression adjustments, along with 30-click rebound adjustment, making it the ultimate choice for serious racers.
Recommended Spring Rates for Subaru Models
Choosing the right spring rates is crucial for optimal performance based on your Subaru model and driving style:
- VA WRX/STI (2015-2021): 8k front / 8k rear for street, 10k front / 12k rear for track/autocross.
- GR/GV WRX/STI (2008-2014): 8k front / 8k rear for street and sporty driving; 10k front / 10k rear for more aggressive setups.
- GD WRX/STI (2002-2007): 7k front / 5k rear for street/light track; 8k front / 6k rear for more aggressive driving.
Conclusion
Investing in a quality coilover system is one of the best ways to enhance your Subaru’s performance. Understanding the features and adjustments available with different coilover systems, particularly those offered by BC Racing and Öhlins, will help you make informed decisions that best suit your driving style and needs. Join us next week as we delve into the nuances of sway bars and how they impact your vehicle's handling.
Stay tuned for more insights from the Grip Guide!