20 MPG combined won’t impress a Prius owner, but it’s what you expect from a mid-engine, naturally aspirated sports car like the 2021 Porsche 718 Cayman GT4. This isn’t a commuter car, though some use it as such. It’s a scalpel built for carving corners, a machine designed to thrill. Fuel economy, while always a factor, is less important than the visceral experience.

City and highway performance

The EPA estimates the 718 Cayman GT4 achieves 18 MPG in the city and 24 MPG on the highway. These numbers reflect the realities of a high-performance engine that thrives on revs and requires a heavy foot to truly exploit its potential. City driving, with its constant stop and go, will result in lower fuel economy, as the engine spends a significant amount of time operating at less than optimal efficiency. The highway figure, while better, still acknowledges this isn’t a car built for coasting. Even at cruising speeds, the 4.0-liter flat-six is ready to unleash its power with even the slightest dip of the accelerator.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2021 Porsche 718 Cayman GT4 at $2,900. This figure is based on driving 15,000 miles per year and using national average fuel prices. Keep in mind that premium fuel is required for performance and engine health, adding to the cost. The $2,900 figure is a benchmark, and your expenses may vary depending on your driving habits and local fuel prices.

Real-world expectations

The EPA estimates provide a guideline, but real-world fuel economy for the 718 Cayman GT4 will likely vary depending on driving style and conditions. Those who frequently visit the track or engage in spirited backroad driving should expect numbers closer to the city estimate, or even lower. Drivers who primarily use the car for longer highway journeys with a restrained driving style may achieve figures closer to, or slightly above, the EPA highway estimate. The car rewards enthusiastic driving, and that enthusiasm comes at a price.

How it compares

Compared to other sports cars, the 718 Cayman GT4’s fuel economy is typical. For instance, the BMW M4 Competition, with its turbocharged six-cylinder engine, achieves a similar 19 MPG combined. The Chevrolet Corvette Stingray, with its larger V8 engine, manages a slightly better 19 MPG combined, however that figure goes down to 15 MPG combined in the Z06 trim. Even the smaller Mazda MX-5 Miata boasts 29 MPG combined, yet it caters to a drastically different breed of performance enthusiast. Potential buyers of the GT4 aren’t cross-shopping it against a Miata. The slightly more efficient Porsche 911 Carrera gets 21 MPG combined, but it lacks the GT4’s handling that comes with the mid-engine layout. For a deeper dive, see 718 MPG across all years.

Tips to maximize efficiency

While the 718 Cayman GT4 is not designed with fuel efficiency as a primary goal, there are steps to minimize fuel consumption. Avoid aggressive acceleration and braking, as these actions place a strain on the engine and reduce fuel economy. A smoother driving style will save fuel and enhance the driving experience.

Use the car’s driving modes effectively. The “Normal” mode will generally provide the best fuel economy for everyday driving, while the “Sport” and “Sport Plus” modes prioritize performance and increase fuel consumption. Selecting your driving mode strategically can allow to you maintain respectable averages.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly and maintain the recommended levels specified in the owner’s manual. A small investment in a tire pressure gauge can yield savings.

Minimize unnecessary weight. Removing excess cargo from the car reduces the load on the engine and improves fuel efficiency. A few extra pounds may not seem significant, and they can add up over time and impact fuel economy, especially in the city. Reducing the weight within the vehicle will also help increase the car’s performance capabilities.

Finally, remember that regular maintenance is critical for engine performance and fuel efficiency. Following the recommended maintenance schedule, including oil changes and air filter replacements, will ensure that your 718 Cayman GT4 continues to run smoothly and efficiently. For all Porsche fuel economy data, see our brand page.