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What Is A Wedge Adjustment In NASCAR?

A wedge adjustment in NASCAR is one of the most mentioned topics in the sport. It is also one of the most important, as it can make or break a car’s handling. They are one of the toughest things to master during a race, and you may be wondering what exactly a wedge adjustment is in NASCAR. 

A wedge adjustment in NASCAR occurs when a pit crew member sticks a ratchet through tubes in a car’s rear window and provides an adjustment to the springs that are in the suspension. They can tighten or loosen the springs, which will affect the car’s handling. 

Below, we will go over what a wedge adjustment is in NASCAR before we explain its importance and how it affects a car’s handling. We will also check out a NASCAR car’s suspension and give you a full explanation of how a wedge adjustment is performed. 

Brief Overview Of NASCAR Suspension

There is a lot to go over here, given the number of car components that make up a NASCAR suspension. The first thing you must realize is that each component can be customized to fit the needs of the car and the driver as long as the customization remains within NASCAR’s specs. This was true in both previous generations and in the Next Gen car. 

Beyond their modifications for the car and driver, the suspension is also modified to fit the demands of a specific track. So, the suspension will not be the same on a road course as it would be on a short track. And when NASCAR races on speedways and superspeedways, the same concept applies. 

Why NASCAR Suspension Is So Important

The short answer is that suspension systems help control the car’s handling. They also help keep the car balanced and planted on the track. This provides a constant challenge for drivers and crew members during a race because there are so many variables outside their control that can negatively affect a car’s handling. 

Each NASCAR track has its fair share of bumps. They all have different banking, many of asphalt or concrete. To even stand a chance at winning the race, NASCAR drivers must be able to control their 3,400 lb (1,545 kg) machines throughout an entire 3 to 5-hour event. And this is why a suspension can make or break a driver’s day. 

What Makes Up NASCAR Suspension?

NASCAR suspension systems are made up of the following components: 

  • Chassis
  • Sway bars
  • Shock absorbers and springs
  • Bushings
  • Steering assembly
  • Tires

Each of these components must remain stable throughout the entire race. If even just one component goes awry, odds are, a driver’s day is over. And you can probably recall times in the past during a race where drivers’ days would end early because of suspension issues. With the cars driving upwards of 180 mph, it puts a lot of pressure on these components

Chassis

It all starts with the chassis, which provides the basis of the car’s skeletal system. It’s practically the skeleton of the car. Our chassis has three frames: The mainframe, the front frame, and the rear frame. The latter two are also known as the subframes. 

You will find each part of the car’s suspension connected to these frames. Below, we will outline each of the frames mentioned in the section above, where they are connected, and their function. 

Sway Bars

NASCAR cars are turning so quickly that they feel a pull to the right when they dive into a turn at a traditional oval track. There is so much pull that the tire grip on the driver’s side can significantly decrease. Sway bars keep the driver’s side tires from losing too much grip by preventing the car from ‘rolling’ to the right, which is why they’re often called anti-roll bars.

These bars serve as the bridge between the car’s body and the chassis. However, not all sway bars are the same, and NASCAR teams will use different types at different tracks. Teams can also adjust the bars’ stiffness to the driver’s liking and on their previous experiences at the track. Sway bars also help keep cars balanced every time they hit a bump. 

Shock Absorbers And Springs

Like sway bars, shock absorbers help the car remain in balance while simultaneously assisting the driver in maintaining a smoother ride. They are also responsible for holding the suspension in place, since something needs to be able to absorb the impact of inevitable beating, banging, and even running over minor debris throughout an event. 

Take off the shock absorbers, and the nuts and bolts wouldn’t be able to withstand the impact of a long race. Any time a car hits a bump, the springs will either expand or contract, allowing the shocks to absorb the negative energy through the spring. They also help keep the tires firmly planted onto the track. 

NASCAR teams have control over determining the correct shock and spring combo for each race. It is not an easy process, but as they gain experience at specific tracks, teams have a much better idea of the shocks’ damping and overall stiffness. 

The piston ultimately decides the overall up and down magnitude of the shock. The piston’s clearance between itself and the cylinders, its medium and bleed holes all work together to control this magnitude. 

Bushings

These are small pieces of rubber shaped like cylinders. NASCAR teams place them in a suspension system’s pivot points and anywhere two components connect, such as in the sway bars. You will also find bushings on your road car, but they are not as stiff as those found on a NASCAR car. 

Bushings must stay in top shape because if they wear even slightly, the driver will feel it. And since the last thing they need is for these simple yet useful components to wear out during an event, teams will constantly inspect them to ensure they remain in pristine shape. 

Steering Assembly

Nothing faces more stress in a NASCAR suspension system than what ultimately controls the car, especially at the brackets and knuckles holding the entire assembly together. If they go out, the driver’s car is going behind the wall and they may as well pack everything up in their hauler and make an early trip back home. 

This assembly connects the car’s arms, chassis, pivoting arms, and tie rod ends, all of which allow the driver to effectively control their car during an event. Knuckles link the assembly to the chassis, while along with the tie-rods, the knuckles further connect the assembly to the car’s wheels. 

Tires

The tires are some of the most important parts of a car’s suspension system. They are the only parts of the cars in contact with the track surface, and they take a lot of strain – hence the need for regular pit stops. The air – in NASCAR’s case nitrogen – inside tires helps them keep their shape and provide the largest possible contact patch with the track for optimum grip.

KEY POINTS

• NASCAR suspension systems are made up of many complex components

• These include things like shock absorbers, sway bars, and even the tires

• They all work together to help the car remain balanced with maximum grip

What Does Wedge Mean In NASCAR?

A wedge adjustment in NASCAR changes the tension on the car’s rear suspension. While you may think this is something teams should adjust before the race begins, it’s not always possible to know what the optimum setup is because of the constantly changing track conditions.

This means that teams have no choice but to adjust it on the fly, which will occur during a pit stop. While the springs are deep within the car’s rear suspension, a set of small tubes in the rear window allows crew members easy access to them. 

How Drivers Know When They Need Adjustments

You may recall watching races where the broadcast relays to television viewers that a driver radioed in about the car’s handling. When this occurs, a wedge adjustment is likely needed to correct the issue. The upside is that the driver knows when an adjustment is needed. The downside, however, is that most drivers don’t know how much of an adjustment they need. 

Therefore, it is common to see drivers call for a wedge adjustment several times during a race. Components outside of a driver’s and their team’s control, like the weather, can also affect a car’s handling. When you watch races that start in the late afternoon and fade into the evening, like the 600-mile Charlotte race, track conditions can rapidly change. 

For this reason, NASCAR drivers could experience handling problems even if the car was handling just fine at the last pit stop. Thanks to advanced technology and the genius of NASCAR engineers and builders, wedge adjustments are fairly easy to make. 

How Are Wedge Adjustments Made In NASCAR?

Wedge adjustments are made in NASCAR through openings in the suspension, often supported by 2 jack bolts, that are accessible with an extended ratchet. These openings allow a member of the team’s pit crew to reach through the window and tighten or loosen the springs with a ratchet. 

How Crews Know When To Adjust

The driver will talk over the radio with either their crew chief or they will relay through their spotter that a wedge adjustment must be made. This allows the crew to prepare an adjustment for the upcoming stop that likely involves a 4-tire change and racing fuel to be added to the car

Since wedge adjustments are common in NASCAR, pit crews expect to make several of them per race. This is especially true if fluctuating weather further provides track conditions to change rapidly throughout the course of the event. 

New Rear Suspensions And Wedge Adjustments

With the Next Gen car, the rear suspension looks radically different from the suspension system of the past. Before, NASCAR cars had what they called a live axle trailing design system, which benefited the cars better on ovals. However, since NASCAR adopted more road course races starting in 2021, a change needed to be made

Hence, the new independent rear suspension system. This was designed to allow cars to turn right better than their Gen 6 predecessors. Drivers gave the new system overwhelmingly positive feedback, and wedge adjustments could still be made in the same way.

What Is A Track Bar On A NASCAR Car?

You will find the track bar under the car at the car’s rear end. Adjusting the track bar either up or down will further adjust the car’s rear axle position and it affects weight distribution. Drivers used to able to adjust the track bar to their liking in the car, but that changed in 2019.

In 2019, NASCAR passed a rule that prohibited drivers from making in-car track bar adjustments based on their feedback from the previous 4 seasons. NASCAR started allowing drivers to adjust the track bar themselves in 2015, but an overwhelming majority of drivers disliked the change in hindsight. This prompted NASCAR to return track bar adjustments back to the pit stop. 

NASCAR’s intention behind allowing drivers to make their own track bar adjustments stemmed from the possibility of running the race for long stretches during green flag laps. Instead of waiting until a pit stop to receive an adjustment, drivers were able to improve their car’s performance on the fly

More Competitive Racing

Also in 2019, NASCAR cut the number of crew members allowed over the wall from 6 to 5. This move, coinciding with NASCAR reverting track bar adjustments back to pit road, made some in NASCAR spheres believe the races would become even more competitive. 

Todd Gordon of Team Penske cited that both crews and crew chiefs would face a daunting challenge. While he acknowledged that before 2015 that a track bar adjustment was routine, the fact of providing an adjustment without a sixth member on pit road would take quite the learning curve. 

The Advantage Of Driver Track Bar Adjustments

While members of NASCAR pit crews are among the fastest in the world at their jobs, the truth is they are prone to making mistakes. And a track bar adjustment can go awry in the heat of a 15-second NASCAR pit stop. Between 2015 and 2019, one huge advantage the driver had was, if a crew member botched a track bar adjustment, they could remedy it at the push of a button.

With NASCAR rules reverting to such adjustments occurring on pit road, any crew member making such an adjustment would need to make absolutely sure that they are making the correct adjustment. With the Next Gen car introduced in 2022, NASCAR stuck with the rule that drivers could not make in-car track bar adjustments. 

KEY POINTS

• Wedge adjustments are made to improve the handling of the car

• They’re fairly easy to make, and pit crews may make several adjustments per race

• Teams can also adjust the track bars to improve handling in the corners

Final Thoughts

A wedge adjustment in NASCAR allows pit crews to adjust the car’s handling. These adjustments are made throughout the race, since the weather can affect track conditions, which affects a car’s handling. Wedge adjustments may seem complex, but they are rather simple, involving just a ratchet twist.