E63 S, M5 Comp, RS6, Panamera Turbo S Power Figures Tested On Dyno

BMW, Porsche, Mercedes, and Audi build some of the most potent models available for mainstream consumers. Their big V8 engines make copious amounts of horsepower and torque, with the automakers claiming some big power figures. A new Carwow video puts their claims to the test by pulling the M5 Competition, E63 S, RS6, and Panamera Turbo S E-Hybrid onto the dyno and running the numbers to find out their actual power-to-weight ratios.

The most powerful car in attendance was the Porsche. The Panamera’s hybrid powertrain with the 4.0-liter twin-turbo V8 engine produces 700 horsepower (521 kilowatts) and 641 pound-feet (870 Newton-meters) of torque. The automaker claims the car weighs 5,180 pounds (2,350 kilograms). The BMW M5 Competition is the second-most powerful model in the test, sporting a larger twin-turbocharged 4.4-liter V8. However, the non-hybrid sedan makes 625 hp (466 kW) and 553 lb-ft (750 Nm) of torque. It’s the lightest, too, at 4,276 lbs (1,940 kg).

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The Mercedes-AMG E63 S features a twin-turbo 4.0-liter V8 engine making 612 hp (456 kW) and 626 lb-ft (850 Nm) of torque. Mercedes says the high-powered E-Class weighs 4,431 lbs (2,010 kg). The Audi RS6 trails the rest of the field in power even though it also sports a twin-turbo 4.0-liter V8 engine. The powertrain produces 600 hp (447 KW) and 590 lb-ft (800 Nm) of torque. It weighs 4,574 lbs (2,075 kg).

The results were all over the place. The Audi delivered 599 hp (446 kW) and 603 lb-ft (818 Nm) of torque from the engine on the dyno, while the BMW surpassed its claimed figures to return 652 hp (468 kW) and 636 lb-ft (863 Nm). The Mercedes also made more power than the manufacturer claimed, producing 636 hp (474 kW) and 690 lb-ft (936 Nm). The Panamera Turbo S E-Hybrid also beat its expectations with 750 hp (599 kW) and 681 lb-ft (924 Nm) of twist.

The dyno results were only one part of the test, with Carwow recalculating their power-to-weigh ratios after pulling the cars onto the scales. The results put the Audi in last at 270 hp/ton. Mercedes took third at 305 hp/ton. While the Porsche was the most powerful car, it only achieved second with its 309 hp/ton rating. The BMW took first thanks to making more power and weighing less than the automaker’s claim returning a 340 hp/ton rating.