In case you missed it, in our First Drive of the 2021 Porsche 911 Turbo S, we said, “The 2021 911 Turbo S is alive, eager, and hungry. It needs its driver, rewards its driver, and it bonds with its driver. This is the car you marry.” So, what changed from the last generation (991.2) 911 Turbo S to the new 992 version? Let’s take a look.
911 Turbo S Engine Specifications
Let’s start with the obvious: their DOHC 24-valve twin-turbo flat-six engines. For the 2021 model, displacement actually went down by 55cc (3,800cc for the 991.2 to 3,745cc for the 992), and the compression was lowered from 9.8:1 to 8.7:1. Yet, horsepower rose by 60 at the same engine rpm (580 hp to 640 hp @ 6,750 rpm), and torque swelled by 37 to 74 lb-ft depending on the overboost conditions of the old car (516 or 553 lb-ft to 590 lb-ft). The new Turbo S does not require overboost conditions; it’s full-boogie full-time. By the way, the new car can send more than half of the engine’s torque, as much as 368 lb-ft, to its new, lighter, and liquid cooled front axle. The overall power density of the 911 Turbo S’ engine increased from 152.6 horsepower per liter of displacement to a staggering 170.9 hp/L. How did Porsche do that? Bigger, higher maximum boost (from 18.1 to 22.5 psi) and “smarter” variable-geometry turbos with increased air intake (rear flanks and rear deck), improved charge air cooling, and more-direct now-symmetrical exhaust flow to the turbos.
What’s The 911 Turbo S’ 0-60 Time?
Combined, the results, according to Porsche, improve the 911 Turbo S’ 0-60 time by 0.2 second and will shave 0.3 second from its quarter-mile time. Applying those estimates to the last 911 Turbo S we tested twice (a 2017-model year 991.2 with different sets of tires), or the hardest launching vehicle we’ve recorded, would mean the 2021 Turbo S should scoot to 60 mph in a scant 2.3 seconds. That would tie the Tesla Model S P100D Ludicrous+, the quickest-ever production car 0-60 we’ve ever recorded. From a stop, it would mean the new Turbo S would cover a quarter mile in 10.2 seconds. And that would put it sixth on our all-time leader board behind: Ferrari LaFerrari (9.7 sec), McLaren P1 (9.8), Porsche 918 Spyder (10.0), McLaren P1 and 720 S (tied at 10.1).
Sure, there’s power and power density, but as we’ve seen with two otherwise identical Mustang GTs (one with a six-speed manual, the other with a 10-speed automatic), gearing can also play a major role in acceleration.
Not that the seven-speed PDK in the 2017 911 Turbo S wasn’t special, but the 2021 Turbo S has an extra special eight-speed twin-clutch automatic. As Porsche’s product spokesperson (and 911, Boxster, and Cayman savant) Frank Wiesmann explained, “The PDK in the new 911 Turbo S features a reinforced clutch with two additional pairs of discs for the purpose of transferring higher ‘torques.’ This means that the  911 Turbo models have a total of six pairs of discs with twelve friction surfaces.” We did some deeper investigation regarding actual gearing, and the new Turbo S has an advantage here, as well. Warning: lots of numbers ahead.