The new horsepower war is fully upon us. It's no longer just about how much fuel and oxygen you can flow through an engine in a quest for a bigger bottom line, it's about getting the most horsepower from the least amount of fuel possible.
That's pretty much on top of the new Corvette Stingray's sporting rival, the Porsche 911, which scores 19 mpg city and 27 mpg highway for 22 mpg combined in 2013 911 Carrera S form. Eking out 2 mpg combined beyond the 911's highway rating is likely a factor of tall gearing and the low-rpm torque of the new LT1 V-8 engine under the Stingray's hood. It's worth noting that the 29 mpg highway figure is above even Chevy's own expectations; the brand had previously estimated 26 mpg highway.
The 29 mpg EPA rating is actually an average of the Corvette Stingray's two standard driving modes, "Tour" and "Eco". In Tour mode, the Stingray rates 28 mpg highway, while in Eco, it scores 30 mpg highway. The main benefit of Eco mode for manual-transmission Stingrays is the activation of Active Fuel Management, cutting four of the eight cylinders under light loads. On automatic-equipped Corvettes, AFM is always active unless the driver engages manual mode via the steering wheel shift paddles. The automatic hasn't yet been EPA rated.
It's important to note that while the 911 and Stingray are right on top of each other on efficiency, the 911 generates 400 horsepower, while the Stingray outputs 455 horsepower--on essentially the same amount of fuel. Manufacturer performance estimates reflect the power differential: Porsche puts the manual-equipped 911 Carrera S's 0-60 mph time at 4.3 seconds; the Stingray's is 3.8 seconds (with the Z51 performance package). Both the 911 and the Stingray offer a seven-speed manual transmission.
The Corvette team certainly sees itself as a leader in this new aspect of performance-engineering competition. "The Corvette Stingray establishes the benchmark for modern performance cars by using technologies to deliver more performance and more miles per gallon," said Tadge Juechter, executive chief engineer for the Corvette. "We expect more and more performance cars will follow Corvette’s example."
Ultimately, gas mileage is still a relatively minor influence on the purchase of a world-class sports car--but when the cheaper, more powerful car is also more efficient, it certainly makes for an interesting consideration.