Penske Racing Shocks Top 5 Suspension Tuning Tips
There is no perfect suspension setup.
Not because it isn’t out there, but the perfect suspension setup is driver-dependent. You can find a near-perfect setup by paying attention to what YOU feel out on the track, but every driver is different. Perhaps you prefer a looser feel, and another driver needs a more stable platform.
Whatever you need to feel confident, you will affect a different part of your suspension setup when you make adjustments. You might gain in one area of your handling and lose somewhere else, and most setups require trade-offs.
In this article, we’ll provide you with our top suspension tuning tips to kickstart your journey to optimizing performance and getting the most out of your vehicle.
Top 5 Suspension Tuning Tips
The key to optimizing your performance on the track is never to stop fine-tuning and developing your suspension setup. There is always room for improvement.
An improperly tuned suspension leads to lost seconds on the track due to handling issues, so it’s worth getting it right at the outset. Having a baseline to work from is essential, and working with your team will make the process easier.
But much like any endeavor, it’s critical to nail the basics of suspension tuning. Start with the suspension tuning tips below. Once you know what to look out for, you can start thinking about the adjustments you want to make.
1. Find the Proper Spring Rate
Spring rates are the crucial first step in achieving a well-balanced suspension.
When springs are too soft or too stiff, everything else is affected—bottoming out, body roll when accelerating and cornering, nose-diving when braking can all be affected by adjustments made to springs.
Shocks complement and control your springs, and they control the speed at which your wheels move up and down by stopping the springs from compressing and rebounding too quickly.
Springs support your vehicle’s weight, and your application, height and weight, driving style, and different track surfaces are all key factors determining the correct spring rate. The way to find your sweet spot is to test and retest.
Lower spring rates equal a softer feel and a more mechanical grip, meaning you might find that your wheels maintain better contact with the track over bumps or divots. Higher spring rates give you a firmer or stiffer feel which might help reduce body roll and lean. But, if your springs are too soft, you might bottom out and have less stability. But again, if your springs are too stiff, your ride quality will suffer.
Finding the proper spring rate is largely driver-dependent. If you feel your car handles better when the springs are softer, that’s your preference.
2. The Right Damping Levels
Despite popular opinion, there is no right or wrong when it comes to damping levels.
Stiffer shock rates slow spring movements, while a softer shock rate allows the spring to move faster. If a shock is too stiff, it can cause the tire contact patch to bounce off the road surface over bumps, making your car or bike feel less predictable. If this is happening, you’ll need to soften your shocks.
However, too soft shocks will make the body of your car or bike bounce after hitting a bump. It’s essential to find the middle ground between comfort and performance, but it’s not cut and dry. You need a highly adjustable shock. You’ll need to take baseline measurements, and you’ll need to test and retest incrementally.
In this free download, we provide both our Standard Shock Build Sheet, which is a great way to keep all your shock builds organized, and a Setup/Lap Time Sheet, a great tool to help improve your communication and record keeping of your chassis setup.
3. Track Conditions
So many outside factors are at play and act on your suspension, so it’s best to prepare.
Different track conditions can seem worrisome but needn’t be with proper adjustments. Remember, keeping a record of your baseline settings and any adjustments you make allows you to tune for adverse race conditions and go back to previous settings once you finish racing.
Smooth or Rough
You might not need to worry about bottoming out and damaging the chassis on a smooth circuit, meaning you could set your shocks and springs up to maintain low ground clearance and a low center of gravity.
Dry and wet weather play a role in the thought process. Knowing what you’ll do to combat wet weather resulting in less grip and tire traction is smart planning. Dry weather can also bring temperature changes, so look at tire pressure and temperature.
Something to think about is adjustable anti-roll bars: when grip reduces, oversteer and understeer are side effects, and the anti-roll bar can compensate.
To Curb or Not to Curb
Are there conditions on the track where you can make up more time vs. others? Setting up your vehicle to absorb curb strikes might seem sensible but might not make your lap time faster.
Is optimizing your suspension for mechanical grip and balance faster? You may have to avoid curbs, but in the end, if it’s faster, who cares? Decide what you can put up within your quest to win.
4. Low and High-Speed Damping
- Low-Speed Damping is generally two to three inches per second or less.
- High-speed is three inches plus.
There is a balance between low and high-speed damping levels and feel.
Generally, you will have stiffer low-speed damping if you like a stiffer balance, more like a kart. This isn’t always a bad thing; if you have more low-speed compression damping, you can generally lower your spring rate, improving your mechanical grip.
High-speed compression is used more for curb strikes or other high-velocity high displacement hits. Typically, this is more for driver comfort, secondary to overall setup lap time. But in cases where large bumps or curbs may be upsetting the optimum driving line, you will have to tune your high-speed damping.
5. Low and High-Speed Rebound
Rebound is just as important as compression. If your rebound rate is off, your suspension might bounce back too quickly and cause a lack of control.
Low-speed rebound is a crucial part of your damping curve. Low-speed rebound significantly affects tire wear, tire temperature, and weight transfer.
Most drivers are also susceptible to low-speed rebound, as it can make the chassis feel stiffer than it might be. If you can imagine a suspension wanting to roll or pitch in a particular direction, if you have too much low-speed rebound, this can significantly affect how quickly the weight transfer happens, directly affecting how fast you’re loading your tires.
Generally, you will want a more linear rebound, but a digressive style rebound can be better in some cases and track conditions.
This part of the damping is less popular to tune. A common high-speed rebound adjustment is made for hard braking conditions. Typically, you want a linear or softer rebound so the tire can follow the contour of the surface of the road.
You want it to move easily and stay in contact as much and quickly as possible.
The problem is if you’re too soft when you get to a tough braking condition, you may see a high-speed rebound velocity. The vehicle can pitch front too quickly, causing an overload on the front tires and unloading of rear tires, which will result in inadequate braking.
It’s All Based on Feel
Do you like a stiff platform, more like a karting feel, or do you want a compliant feel, something that moves around more? If you determine what you want to feel from your car, you’ll have a baseline and be able to make adjustments that bring the best results.
The goal is to understand each part of the suspension and what each part is trying to do. Then figure a way to set all these pieces up, so most importantly, they complement what the driver wants to feel. Then you can look at what the tires and other vital factors bring and how they give you an advantage.
One Part of a Whole
You can take a lot away from this post. The above suspension tuning tips are just a few areas to focus on initially. When you start adding complex suspension components, things like 4-link, central dampers, sway bars and then make camber adjustments and toe settings, you realize there is no one correct way to set up your suspension.
As you experiment with your setup and run tests, you might come up against some suspension issues, and we have a webinar dedicated to the most common ones.