What Makes NASCAR Engines Rev So High?

What Makes NASCAR Engines Rev So High

In motorsports, the performance and specs of a car's engine are of the utmost importance. This is especially true in NASCAR, which has tight constraints and specific tolerances that must be met. The engines that make NASCAR models scream around the track tend to have very high RPMs. So, why do NASCAR engines rev so high? Keep reading to find out.

Why Do NASCAR Engines Rev So High?

NASCAR engines rev so high because it is an efficient way to produce the most power. To reach and maintain the speeds seen at iconic tracks such as Talladega and Daytona, an engine has to output a massive amount of horsepower. Increasing the revolutions per minute a car’s engine makes maximizes the power output, resulting in greater acceleration and a higher top speed.

NASCAR Engine Design

There several unique design elements that allow NASCAR engines to rev so high:

  • Strong, lightweight engine blocks
  • High-compression tuning
  • High-octane fuel
  • High bore-to-stroke ratio
  • Oversized head ports
  • Solid lifter cams
  • Dry sump oil systems

How High Do NASCAR Engines Rev?

An average street model sedan can run at around 7000 rpm max, and constant use at this revolution rate will destroy the engine. In contrast, a NASCAR engine is designed to operate at 10,000 rpm without suffering damage or degradation.

The engineering of the eight-cylinder engines and fuel injection systems used in NASCAR engines are a major part of why they can rev so high. While the horsepower and revolutions the engines produce are incredible, they could be higher. Restrictions on piston length, cylinder space, and tapered spacer requirements at certain tracks are used by NASCAR to limit horsepower and engine power to make the sport safer and reduce the rate of fatal collisions.


Are NASCAR engines the same as street car engines?

The engines used in NASCAR racing vehicles are far from those you would find in the street-legal versions of stock cars. Most cars on the road today use a four-cylinder, unmodified engine. This means four pistons are used to generate the mechanical power needed to drive the car forward. A NASCAR engine uses a V8, or eight-cylinder engine, with four more pistons firing than most standard street cars. Beyond the number of cylinders firing within a NASCAR engine, there are upgraded fuel injection systems and other modified components. These components are designed to increase the engine’s durability when running at incredibly high RPM and to meet certain requirements NASCAR has in place for a car to be allowed on a track.