Why Did NASCAR Reduce Horsepower?

Throughout the history of NASCAR, there has been a constant struggle to maintain a balance between speed, competition, and keeping fans happy. If you’re new to the sport, you may be wondering what changes are made because of this, and if this is why NASCAR reduced horsepower.

The reason NASCAR reduced horsepower was to increase competition, improve safety, and reduce wear and tear on the engines. NASCAR hopes to achieve all that with their latest car generation. The Next Gen engine actually has more horsepower than the previous Gen 6 engines.

Of course, any change in NASCAR has proponents and detractors. Horsepower management is no different. Some question why NASCAR has gone in this direction, while others wonder about how effective the changes have been. Below is a rundown on why NASCAR has opted for the horsepower arrangement it has. 

What Was The Most Powerful NASCAR Car?

The most powerful NASCAR car was the 2007 Chevrolet car, fitted with the Chevrolet R07 engine that could produce over 900 horsepower. It was a V8 engine, like the current setup, and it was built specifically for use in NASCAR. It produced much more power than the current 670 HP.

Traditional Power

While there have been immensely powerful NASCAR vehicles, it has not always translated into speed. NASCAR runs less horsepower today than it did in the past, but the speed of the cars has not been altered all that much. A powerful car in the traditional sense might have a giant engine but not be very fast

A NASCAR race car can go from 0 to 160 in about 9 seconds. That has remained fairly consistent over the years with only a few specific years having any negligible difference. It has not mattered all that much how much horsepower a vehicle possessed.


The fastest overall vehicle in NASCAR ran between 1987 and 1989. It was a Ford Thunderbird and was driven by Bill Elliott. In this car, Elliott clocked in a top speed at Talladega of 212.80 mph and a top speed at Daytona of 210.63 mph. Elliott ran the top speed at Talladega during qualifications for the Winston 500 in 1987. 

Elliott’s Thunderbird was a tube-frame stock car that weighed 3,700 pounds. The engine was a 351 cubic inch V-8 with 625 horsepower. That horsepower was not close to the 2007 Chevrolet engine, even though the 2007 cars couldn’t reach the speed Elliot achieved. 

NASCAR Changes

The speeds attained during the mid-1980s prompted NASCAR to introduce restrictor plates to the engines to slow the cars down. Restrictor plates restricted the amount of oxygen that could get to the engine, thus reducing the horsepower

Many, like Dale Earnhardt, felt the restrictor plates bunched cars up and made large wrecks more likely. The restrictor plate introduced back then (now the tapered spacer) held the engine horsepower to about 410 on superspeedways. For that reason, no NASCAR vehicle has officially broken Elliott’s record

How Much Horsepower Do The Next Gen NASCAR Cars Have?

The Next Gen NASCAR cars have approximately 670 horsepower on most racetracks. However, it varies for the superspeedways, clocking in at 510 horsepower. This is an attempt to keep the overall speed of the cars lower without completely diminishing the pace of the races.

NASCAR brought in the Next Gen car in 2022 as a replacement for the Gen 6, which was used from 2013 through 2021. The change affected the entire car and chassis for the Cup Series. The goal of the Next Gen car was to give the 3 automakers in NASCAR (Chevy, Ford, Toyota) a vehicle that closely resembled their street equivalents. 

It is also hoped that the Next-Gen vehicle would improve competition at all racetracks and allow for rapid technology development and sharing. The Next Gen car was introduced at the Busch Light Clash at the Los Angeles Coliseum. 


After years of assessment, NASCAR decided to go with a high downforce aerodynamic package. The Next-Gen car runs a 4” spoiler on most tracks. However, on the superspeedways (Daytona International Speedway, Talladega Superspeedway, and Atlanta Motor Speedway) the car has a 7” spoiler to help keep it on the track and its speeds at a manageable level.


The Next Gen car actually has more power than the Gen 6, although it is still down on those used in the 1990s and 2000s. It offers approximately 670 horsepower at most racetracks. For the superspeedways, the package will have engines with 510 horsepower. Less horsepower on superspeedways is another attempt to keep speeds lower to improve safety.

Why Did NASCAR Lower Horsepower?

NASCAR lowered horsepower on its cars for a variety of reasons, including safety concerns, to lower the overall speed, to create better competition, to attract more teams and investors, and to help reduce long-term engine damage. The current cars produce around 670 HP, which is more than the Gen 6.

For a period from the late 1980s through the mid-2000s, NASCAR horsepower was insane and so were the speeds that were being reached. The Ford Thunderbird that Bill Elliott used at Talladega to set the NASCAR speed record was more the norm than the outlier. It was routine at superspeedway races for drivers to hit more than 205 miles per hour.


Whether drivers liked it or fans applauded it, one motivator for making a horsepower change in 2013 was safety. The packages teams were putting together were running faster than before as technology streamlined just about every aspect of a racecar. That streamlining allowed teams to find speed but also increased the risk of spectacular injury and life-threatening crashes.

One issue was that as vehicles became more aerodynamic, they also became less stable. Less stable vehicles tended to become airborne with increasing frequency. Several high-profile crashes that injured major NASCAR drivers led the organization to start examining speed and aerodynamics as a new generation vehicle was created.

Part of that equation was less horsepower, as NASCAR believed that lower horsepower meant less speed and less speed meant fewer crashes. Several high-profile drivers challenged this assumption. They argued that lower horsepower would bunch strong and weak vehicles together and make large crashes more common.

Speed Control

Another factor in the decision to lower horsepower was the perceived need to control the speed of vehicles at everything from mid-sized raceways to superspeedways. Towards the end of the 2000s, the speeds even at relatively slower tracks like Kansas and New Hampshire had begun to rise significantly. 

This was because the teams had learned how to get as much speed out of the vehicle via modifications as possible. The result was vehicles that went through corners faster and thus hit straightaways faster.

At superspeedways, the speeds started to approach pre-restrictor plate days. Even some drivers voiced concerns that the cars were too fast for the drivers’ safety. After a couple of high-profile crashes at some of the larger tracks, including Talladega, NASCAR began to look at reducing horsepower as a further way to reduce speed.

Create Competition

Lowering the horsepower of the cars was designed to open the door for race teams that did not have exceptional equipment to have a chance at competing for higher positions. However, clearly those with the best drivers and the biggest budgets would still regularly find themselves at the front.

Attracting Teams

Running even 1 NASCAR vehicle is incredibly expensive. Some figures put a single car at over $25 million per year. For many people, even wealthy investors, that figure was too high to justify the return. The thinking was that lower horsepower engines would be less expensive, and thus more could afford to invest in a NASCAR team.

Better Track Competition

The better cars almost always were getting ahead of lesser equipped cars and by mid-race, the lead between first and the last vehicle could be sizable. At some tracks, the only way someone racing in the middle of the pack had at getting to the front of the race was if there was a caution.

The disparity was not a reflection of driver skill, but the caliber of equipment. The big names had equipment that blew away teams that did not have top-of-the-line equipment. NASCAR lowered horsepower to help correct that gap. The thinking was that the lower horsepower would put all vehicles on the same plane in terms of speed.

Final Thoughts

NASCAR reduced horsepower for a variety of reasons, including driver safety, engine wear and tear, competition, controlling top speeds, and attracting more teams. NASCAR has constantly modified horsepower, but the Next Gen car actually offers more horsepower (670 HP) than the Gen 6 (550 HP).