Why Does NASCAR Use Slick Tires?

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NASCAR uses slick tires instead of grooved tires. While slick tires are not cheap, they are beneficial for NASCAR teams. They will on rare occasions opt for grooved tires for part of an event. There are several reasons why NASCAR use slick tires.  

NASCAR uses slick tires because their lack of treads gives their cars more traction on the track surface, as they have a larger contact patch. They also hold their form better when wearing down, which makes them faster than grooved tires seen on road cars even when they’re beginning to wear out.

Below, we will explain in full detail why NASCAR tires have no tread. We will also discuss when NASCAR forgoes slick tires in favor of grooved tires, and discuss the various types of tires NASCAR cars can use.

Why Do NASCAR Tires Have No Tread?

NASCAR tires have no tread because smooth tires provide more grip on a dry track. Slick tires have a smooth surface, and this allows for maximum contact between the tire and track surfaces, giving drivers more grip and allowing them to race faster. 

While NASCAR’s Next Gen cars further resemble their production line counterparts, several key differences exist. One of which is the type of tires both the Next Gen and former generations of cars used. While the Next Gen’s wheels are larger than previous generations, they still use treadles (or slick) tires instead of grooved tires that you would place on your production car. 

And while driving with slick tires isn’t ideal for your road car, it is a smart strategy in NASCAR. You need tread on your tires because road conditions vary thanks to the weather. The more tread you have on your tires, the safer you are in rain and even snow. 

NASCAR rarely races in wet conditions, so therefore they do not need tread on their tires. Slick tires give NASCAR cars better traction, and their cars perform at their best when more of the tire touches the track surface. This is down to the larger contact patch offered by slick tires, as treaded or grooved tires have parts of the tire that are not in contact with the track surface.

Are Slick Tires Faster?

Slick tires are faster than grooved tires due to the larger contact patch touching the track. However, this is only the case on a dry track. Speed is one major component that wins races, and NASCAR teams do everything to augment their car’s speed within the organization’s specifications.

Quick Fact

Teams can spend in excess of $20,000 per race on slick tires per race, which equates to $720,000 per year

One downside to slick tires is that they wear down much faster than grooved tires. This, as you can guess, is one reason NASCAR teams are constantly changing tires during a race. This means teams spend a lot of money on tires every race to ensure their drivers are as fast as possible.

Despite constant wear, knowing when to pit is not a chess game for NASCAR teams. Typically, NASCAR tires remain fast for the duration of a tank of fuel. This is why when drivers pit, you see the gas man filling the fuel tank while the jackman, tire carriers, and tire changers change the tires. 

Does NASCAR Race In The Rain?

NASCAR does not race in the rain because NASCAR cars nearly always use slick tires and rarely have working windshield wipers. However, NASCAR races may take place in damp conditions, and this calls for the use of specific tires designed for a wet track. This only happens on road courses, not ovals.

If there is a thunderstorm in the area, NASCAR further mandates that the track surface must be dry, and lightning has not been spotted in the area for at least 30 minutes. NASCAR races are stopped for lightning not just in the interest of driver safety, but also for fan safety. 

24-Hour (Or Longer) Rain Delays 

Sometimes, rain will be so heavy that it is impossible for NASCAR to continue racing that day, so they move the event to the following afternoon. This is why you may see a race occasionally occur on a Monday. Other times, they may delay a race even longer. 

Back in 2020, the Autotrader EchoPark 500 at the Texas Motor Speedway was pushed back 3 days and finished on Wednesday, the longest rain delay in modern NASCAR history. However, it was not the longest in the history of the sport. 

The longest delay occurred on March 11th, 1973, when rain washed out a race at Bristol Motor Speedway after 52 laps. The delay lasted 2 weeks, and drivers finally finished the race on March 25th. Cale Yarborough was the eventual winner. 

Delayed Two Consecutive Days

Before NASCAR postponed the 2020 Autotrader Echopark Automotive 500, the 3M Performance 400 at Michigan International Speedway became the first race in NASCAR’s modern era delayed 2 days in a row

Since the race finished on a Tuesday, teams spent less than 24 hours in their predominantly North Carolina race shops before hauling their rides to Bristol Motor Speedway for a Saturday event 4 days later. Fortunately, with Bristol being such a close track, this didn’t negatively affect teams

What Do NASCAR Rain Tires Look Like?

NASCAR rain tires look a bit like your standard road car’s tire, in that they are radial tires with tread blocks on them. These tread blocks help evacuate water away from the tire while still providing enough of a contact patch to give the driver enough grip in the wet. 

While you may think NASCAR tires all look the same, there are actually a number of stark differences between them. Goodyear makes 3 primary sets of tires for NASCAR cars: Slick tires, dirt tires, and rain tires. 

When NASCAR believes the track will be damp with moisture, they prepare for what they call a wet start. They also have damp starts, which occur when bits of moisture are present on the track. However, NASCAR can deem the track not race-ready if there is too much moisture on a track. 

But if they believe the wet conditions will not adversely affect the cars, NASCAR mandates that their teams use rain tires when preparing for wet starts. They must also install working windshield wipers and activate a rear flashing light. 

For a damp start, each team’s crew chief decides whether to install rain tires. NASCAR will still mandate the flashing light, and they may also require teams to install windshield wipers. After the race begins, teams may switch back to their normal slick tires. 

Rain Tire Aesthetics

When mandated, NASCAR requires its teams to have 4 sets of rain tires available. Unlike slick tires, rain tires contain tread that will channel away moisture on the track, much like that of your road car. 

When watching the cars race, you may not be able to tell the difference between rain tires and their slick counterparts. But you only need to look at the Goodyear labeling on the tires. If the label is white, then you know NASCAR is using rain tires for that particular event. 

NASCAR Rarely Races In Wet Conditions

Most of the time, you will see NASCAR end or postpone a race in wet conditions as they are not feasible for the cars to race. You’ll never see a wet race on an oval, but you might see one on a road course.

NASCAR’s Cup Series has never completed a full race on wet surfaces. However, they ran feasibility tests at Watkins Glen and Martinsville in 1995 and they also used the tires in several practice and qualifying runs. They did race through a rainstorm at Road America in 1956 with no special tires. 

Dirt Tires

NASCAR runs 1 dirt race per season, dubbed the Bristol Dirt Race. You may have seen a close-up of the tires at the Bristol Dirt Race, and one glance tells you that they are different. These tires contain block-style tread. 

And just like the grooved tires NASCAR uses on damp and wet surfaces that channel water, dirt tires bite through Bristol’s dirt-covered track. These give NASCAR cars more grip on the dirt surface. 

Further, these are not radial, but bias-ply tires, something NASCAR and its tire supplier Goodyear deviated from in 1989. Before the dirt track’s introduction, none of the Cup Series drivers at the time used bias-ply tires, so it marked an adjustment for all NASCAR teams. 

Key Points

Most of the time, the tires used in NASCAR are Goodyear Eagle slick tires

NASCAR rain tires will only be used on road course tracks, never on ovals

NASCAR dirt tracks require special, tough-construction tires 

Final Thoughts

NASCAR uses slick tires because they give cars better traction. They also maintain their shape better than grooved tires as they wear, which makes them faster. If NASCAR deems a wet track surface to be safe, they will use grooved rain tires for a portion of the event, but only on road courses.