Convertibles are often less nimble and sporty than their hardtop counterparts. The lack of a roof and its structural rigidity increases the car’s drag and weight, making a difference in how it performs. A CarExpert YouTube video tries to determine how big of a difference there is by pitting the Porsche 911 Turbo coupe against the convertible version in a series of drag races.
The two are identical where it counts – a twin-turbocharged 3.8-litre flat-six engine produces 572 bhp (426 kilowatts) and 553 pound-feet (750 Newton-metres) of torque. Power routes through an eight-speed dual-clutch to all four wheels in both. The only difference is their roofs and their wight, with the coupe weighing about 60 kilograms (132 pounds) lighter than the convertible.
Gallery: 2021 Porsche 911 Turbo: First Drive
The two compete in five drag races with varying parameters. The first race with the convertible’s roof up saw the car complete the race in 11.5 seconds compared to the coupe’s 11.4-second time. The second race puts the roof down, and somehow both are quicker, returning the same 11.1-second time.
The second two races equalise the cars’ weight by adding ballast to the coupe, and both cars improve their times again, with the top-up 911 Turbo convertible beating the coupe by 0.1 seconds. The convertible returns the same 10.8-seconds time with the roof down in the next race, though it takes the coupe 11.0 seconds to finish. The final race has the cars swapping lanes, and the coupe wins again, crossing the finish line in 10.9 seconds.
Picking a pair of 911 Turbos for this test might not have been the best car to highlight the differences between a hardtop and a convertible. The 911 Turbo is a rocket in both configurations. A lap around a race track might have been a better test than a drag race, possibly better highlighting their performance differences.
Source: CarExpert / YouTube