Every part of a modern racing car is optimized for maximum performance – including the fluids it contains. Specialized racing oil is a must in the paddock, but is it a good idea to use it in your street car?
“Engineering Explained” presenter Jason Fenske answers this question in this video and speaks to engineers from Mobil1 (who also sponsored the video), engine builder Roush Yates Engines, and NASCAR team Stewart-Haas Racing.
First of all, Fenske emphasizes that racing engines don’t have much in common with road vehicle engines. Bumper V-8s such as those used in NASCAR disappeared from the average American car decades ago, and racing engines generally have an entirely different duty cycle. They’re flogged (a NASCAR V-8 can spin up to 10,000 rpm and spend 90 to 95% of a race at full throttle) but also have relatively short maintenance intervals. NASCAR engines have oil changes about every 500 miles and are only expected to last about 1,500 miles, noted Fenske.
Ford Mustang NASCAR Xfinity Series racing car
NASCAR oil is also pretty unrestricted (the rules may vary depending on the racing series), which gives teams more leeway to seek competitive advantage, Fenske said. Teams tend to use thinner oils to reduce frictional losses and maximize performance. That’s not great for longevity, but keep in mind that the engine only needs to last 1,500 miles. On the other hand, road car engines are expected to last hundreds of thousands of kilometers, so this type of compromise is not an option.
However, racing oils and road car oils have some things in common. They use many of the same additives like detergents, dispersants, defoamers, antioxidants, and rust inhibitors, Fenske noted.
The difference, however, is in the details. Oils used in road vehicles meet a long list of regulations and requirements set by individual automakers. Even in NASCAR, where the rules for oil are pretty loose, teams can optimize an oil for a specific engine design. It is really this process that racing oil works, and it’s just not practical for individual road cars. Unless you have at least your own laboratory and a lot of patience.