Audi RS 7 and Mercedes-AMG C63 Duke It Out Over the Quarter-Mile; It's a Hybrid Surprise

The AMG C 63 is a nameplate filled with historical resonances, and the latest member in this illustrious family is a fire-lightning mongrel, otherwise known as a hybrid among the car addict circles. Stepping up to the challenge is a classic Audi RS that still pledges allegiance to internal combustion. Better yet, it’s a V8.

While the Mercedes-AMG is a wagon that can haul people and luggage everywhere, the Audi is not an Avant, as we might have expected from this carwow event, but the full-fledged RS 7. The fastback sedan has twice as many cylinders as the inline-four Merc. It has a bigger price tag (by one-third, mind you) than the other German contestant (which does not come cheap, at £100,000 / about $130,000, at the July 2024 exchange rate).

The Lord of the Four Rings is armed with a fiery four-liter twin-turbo (the classic setup of all Ingolstadt performance products) that produces 630 hp (639 PS) and 627 lb-ft (850 Nm) for all four wheels to play with. It’s quite a hunky chunk of German automotive engineering, tipping the scale at 4,553 lb (2,065 kg).

It’s still below the Mercedes because the hybrid powertrain implies battery packs, which aren’t cheap. They put a heavy toll on the car (pun intended), with a body mass of 2.2 tons (4,828 lb). The two-liter inline four-cylinder turbocharged engine is maybe half the size of that in the Audi, but it carries a broadsword of an output: 469 hp, 402 lb-ft (476 PS, 545 Nm).

I know it's not on par with the performance figures in the Audi, but that’s only half the story. The Mercedes has another motor on the rear axle that draws its vitality from the 4.8-kWh lithium-ion battery pack. The electric output adds 201 hp and 236 lb-ft (204 PS, 320 Nm) for a system total of 670 hp (680 PS) and 752 lb-ft (1,020 Nm).

Yes, the sum of the two torque figures doesn’t match the number advertised by Mercedes-AMG. The electric motor doesn’t do anything through a nine-speed transmission, like the combustion unit. Instead, it has a two-speed transmission. More power, torque, and electric spontaneity for off-the-line take-off – the Merc is the favorite.

The 305 bhp/ton power-to-weight ratio of the RS 7’s is just under the AMG’s rating of 310 bhp/ton. Yet, the posh fastback (Sportback, in Audi-ese) gets across the quarter-mile first, in 11.3 seconds. Two-tenths later, the Mercedes kills the stopwatch, and we can burn those paper calculations and blame the drivers for this non-abiding-to-calculations performance. Surprisingly, from a rolling start at 50 mph / 80 kph in third gear, the Mercedes doesn't run out of breath and keeps the Audi in its wake for the entire half-mile sprint.