We all know how pivotal the right setup can be, so I thought I'd share my configurations, especially after some of you reached out asking for details.
Once you start running racing slicks on the C8 Corvette the OE suspension does not live up to the task. This is a good starting point to prepare a C8 Corvette for racing competition.
- Low Rebound: 4
- High Rebound: 6
- Low Compression: 4
- High Compression: 5
- Low Rebound: 4
- High Rebound: 6
- Low Compression: 6
- High Compression: 7
I've found this configuration to be a very good initial track setup. It could be stiffer, or softer, to suit your tastes but I left it right in the middle and focus on the drive. It's also the manufactures' recommended settings, go figure.
Tighter adjustment of the rebound or compression stage leads to a more direct driving experience, whereas a softer adjustment results in higher comfort. Your car will perform well within a wide range. The final adjustments are for driver comfort, feel, feedback and dynamics.
The primary function of dampers is to control the kinetic energy of the springs, converting it into thermal energy that's then dissipated. Without dampers, springs would continue to oscillate, causing the car to bounce continuously
Compression Phase: During this phase, the damper is compressed, and the piston inside moves through the damper fluid. Adjusting the compression resistance affects:
- Wheel Load: Firmer compression improves the tire's contact with the road, especially during cornering. This counteracts the loss of wheel load caused by centrifugal forces during rapid changes of direction.
- Suspension Travel: Too soft a compression and the suspension might "bottom out" over bigger bumps or during hard braking.
Rebound Phase: Post-compression, the damper returns to its original state. The rebound adjustment governs:
- Wheel Traction: A quicker rebound ensures that the tire returns to the road quickly, improving traction and stability.
- Body Movement Control: By controlling the rate of extension, the damper aids in managing the body's pitch during acceleration and its dive during braking.
- Adjust by turning clockwise (+) for higher damping. Range: 0-13 clicks (14 positions). Effect: A lower setting brings more comfort at low speeds but sacrifices stability and precise steering at higher velocities. Conversely, a higher setting enhances the front axle's handling. Still, it might decrease traction in certain conditions, compromising driving comfort.
- Adjust counter-clockwise (+) for increased damping. Range: 0-13 clicks (14 positions). Effect: Increasing the setting curtails rebound post strong compression, boosting body control. A decreased setting allows the wheels to react faster over obstacles, increasing comfort and reducing wheel strain.
- Clockwise (+) turns increase damping. Effect: A harder setting on the front axle sharpens steering responsiveness, making the vehicle feel more aggressive. A softer setting, however, results in gentler steering behavior. On the rear axle, increasing compression stabilizes the vehicle during direction shifts or counters oversteer tendencies. Too much compression, though, can cause discomfort and diminish grip.
- Adjust counter-clockwise (+) for enhanced damping. Effect: This setting caters to the vehicle's response to fast road conditions like curbs, rough terrains, or depressions. Upping the compression provides superior body support and control, particularly through uneven stretches. Reducing it, on the other hand, amplifies comfort during such transitions.
The adjustment wheel operates a precision mechanical valve. Please ensure not to force the wheel beyond its setting limit, as doing so can harm the internal mechanism
It's imperative not to have one axle set very hard while the other is set very soft. This can lead to unpredictable vehicle behavior
Make changes in 2-3 clicks at a time. Less may not be noticed and more may over shoot your goal
Make changes to one axle at a time (Front/Rear)
Make changes to one setting at a time (COMP/REB)
Start from the Manufactures recommended settings. If those are unknown, start with all settings near the center of the available range and work out in each direction 3 clicks at a time on one axle (Front/Rear) and one setting (Comp/Reb) on both wheels (Right/Left) until the dampener starts to behave
Sway Bar Settings:
Street (AFE Recommended)
- Front: 3 (Stiffest)
- Rear: 1 (Soft)
Track (As Tested)
- Front: 3 (Stiffest)
- Rear: 2 (Medium)
I've leaned towards a stiffer front end to really dial in the steering precision and handle the increased load generated by the slicks. The medium setting at the rear complements it by allowing just a bit of movement, without making the rear wild.
Pro Tip: Stiffer roll resistance will demand more from the tires. When the tire’s grip is overloaded, they will begin to slip.
Manipulating when the front or rear tires slip can make the vehicle understeer, oversteer, or handle neutral.
Think of it as the higher the stiffness, the earlier the slip
- If the front slips first, you will have understeer.
- If the rear slips first, you will have oversteer.
- If both front and rear slip near the same time, you are driving too fast and sliding off track!
Although many people might think that a perfectly neutral or slight oversteer would be ideal for a race car, having a small amount of understeer helps a professional driver find the limit of grip. This is especially critical for high-speed circuits
Definition: Body roll refers to the tilting or leaning of the vehicle's chassis towards the outside of a turn when the car is cornering. It's a natural consequence of the centrifugal force acting on the vehicle's center of gravity (CoG) when turning.
Causes: As a car corners, the weight transfers from the inside wheels to the outside wheels due to inertia. This causes the suspension on the outside to compress and the suspension on the inside to extend, leading to body roll.
Effects: Excessive body roll can lead to reduced grip, especially if the tires on one side of the car are lifted off or aren't making optimal contact with the road. This compromises the car's handling and can result in understeer or oversteer, depending on various factors.
When you notice a tire lifting off the ground during aggressive cornering or when navigating chicanes on a race track, it's not just a spectacular sight – it's also a significant telltale sign about your car's suspension setup
The culprit is often found diagonally across the car. When the right rear tire, for example, lifts off the ground, it indicates that the left front spring might be too soft. This soft spring isn't adequately resisting the weight transfer, which results in a reduced vertical load on the diagonally opposite tire
By increasing the spring rate on the diagonal opposite side, you can better balance the forces acting on the car
Transfer More Load: A stiffer spring rate will transfer more load across the diagonal axis of the car, aiding in keeping that lifted tire planted.
Improve Traction: With all four tires maintaining better contact with the ground, you can maximize your grip, reducing the chances of unwanted wheel spin or loss of control.
Enhance Steering Precision: Ensuring all tires maintain consistent contact helps in providing more accurate feedback through the steering wheel, leading to better cornering precision.
Function: Sway bars (anti-roll bars) connect the left and right suspensions and act as torsion springs. When one side of the suspension moves, the sway bar exerts a force to resist that movement, thereby reducing body roll.
Tuning Balance: The stiffness of sway bars can be adjusted or different bars can be installed to fine-tune a vehicle's handling:
Suspension Independence: While they reduce body roll, sway bars also decrease the independence of the suspension on each side of the vehicle. This means if one wheel encounters a bump or dip, the sway bar can transfer some of that motion to the opposite wheel, potentially reducing grip in certain situations.
Spring and Damping Rates: The effectiveness and behavior of sway bars are influenced by the spring and damping rates of the suspension. For instance, a vehicle with very stiff springs might not need as aggressive a sway bar to control body roll
Geometry: Suspension geometry, including elements like camber, caster, and toe, will interact with sway bars in determining how the vehicle behaves during cornering
Quick Adjustments: One of the advantages of sway bars in a racing context is that they can be quickly adjusted, allowing teams to fine-tune handling and balance other suspension and tire adjustments
Consistency: By mitigating body roll, sway bars can help maintain consistent tire contact with the road, leading to more predictable and controllable handling
Running on Michelin Slicks. There's just something about these that give the C8 that extra edge. Superb grip, excellent wear rate (just kidding, they don't), and they work brilliantly with the suspension setup (serious bout this one). They may or may not be legal at your next race and I'm also testing some Hoosiers here shortly
They REQUIRE a full race suspension and generate considerably more forces than any DOT tire is capable of. You have to tune the suspension to match.
The primary advantage of slick tires, including the Michelin S8M, is the amount of grip they provide. With a smooth surface free of any tread pattern, they have a much larger contact patch with the asphalt compared to regular road tires. This means there's more rubber in contact with the road, which translates to increased grip.
Better Heat Performance:
Racing slicks, like the S8M, are designed to operate at high temperatures. When warmed up, the rubber compound becomes tacky, further enhancing grip. This is why you'll often see racing teams using tire warmers before a race.
Enhanced Responsiveness and Predictability:
The consistent and large contact patch means that slicks respond very predictably to steering inputs, which is crucial for drivering at high speeds.
The "S8M" in Michelin’s tire denotes a specific compound. Different compounds offer varied balances between grip and longevity. Knowing when to use a specific compound can make a significant difference in race strategy.
Limitations and Considerations:
Wet Performance: Slick tires are not meant for wet conditions. Their lack of tread means they can't displace water, leading to hydroplaning. For wet conditions, you MUST switch to "wet" or "intermediate" tires with tread patterns.
Racing slicks have optimal performance within specific heat cycles. After a certain number of heat cycles (heating up and cooling down), the tire may not offer the same level of peak performance.
High-performance racing slicks like the Michelin S8M come at a premium. They're an investment meant strictly for track use.
If you're looking to maximize your track times and overall performance with the C8 Corvette, it’s all about Tires and Suspension. I've tried to also emphasize the interconnected nature of suspension components and how a seemingly unrelated part of the car can influence the overall handling balance. Every component should complement the other, and after countless hours and laps, this setup works wonders for me. No other modification to your C8 will decrease your lap times more than these modifications done together correctly.