Audi R8 vs Porsche 718: Specs Compared

Running cost over five years: at the EPA's 15,000-mile-a-year assumption the Porsche 718 burns about $3,150 of fuel annually against $4,200 for the Audi R8. That $1,050 yearly gap compounds to roughly $5,250 over five years and $8,400 over eight — often more than the price difference between two trims of the same vehicle, and the single largest running-cost line item separating these two.

City and highway economy: the Porsche 718 leads in both cycles — 21 mpg city and 27 mpg highway against 14 and 25 mpg — so its fuel-efficiency advantage holds whether you commute in traffic or cover long highway miles.

Powertrain choice: the Audi R8 is recorded with 2 distinct engine configurations (SIDI & PFI, SIDI), the Porsche 718 with 1 (SIDI). Across 24 recorded Audi R8 configurations and 91 for the Porsche 718, the wider the engine spread the more the real-world fuel efficiency depends on which version you actually buy, so check the specific model year and drivetrain rather than the headline number.

Drivetrain and class: the Audi R8 is offered with Rear-Wheel Drive, All-Wheel Drive, the Porsche 718 with Rear-Wheel Drive. All-wheel drive typically costs one to two mpg combined against the same vehicle in front- or rear-wheel drive, which is worth remembering when the gap between these two is small. The EPA classes them as Two Seaters and Two Seaters respectively — the class drives the interior volume, cargo space and passenger space each one is measured against.

Tailpipe emissions: at their cleanest configurations the Porsche 718 emits 375 g/mile of CO2 versus 497 g/mile for the Audi R8. Emissions track fuel consumption almost exactly, so the cleaner vehicle here is also the cheaper one to fuel.