Everything You Need to Know About the Porsche 911's New Hybrid Engine

We’re assured an all-electric Porsche 911 is still some years in the future, but fans have long fretted about interim attempts at mild electrification of their beloved Carrera. Well, now that we’ve examined the technology and deposed the company’s engineers about its inner workings, we assure you the new 3.6-liter single-turbo 2025 Porsche 911 Carrera GTS T-Hybrid is going to be just fine. (The basic 992.2 Carrera is new, too; you can read about it here.)

Why Start with a Bigger Engine?

Much of the motivation behind this and many other powertrain updates happening at Porsche right now comes from impending European legislation that essentially does away with fuel enrichment of the sort that all engines (especially turbos) have long used under high-load conditions to cool the intake charge and exhaust.

Maintaining a strict 14.7:1 air-fuel ratio (known as Lambda=1) at all times typically requires dialing back the spark advance to prevent harmful knock, reducing peak output numbers of an engine that had been running rich at full load. Displacement is the replacement for this lost power, un-throttling the engine to allow in more air (and hence more fuel) to claw back that power. Toward that end, this “new-from-scratch” 3.6-liter features over-square (97 x 81 millimeters) cylinders to enhance breathing, and 10.5:1 compression to enhance both power and efficiency. For now, the central direct fuel injection carries over. The block and cylinder heads also integrate things that formerly bolted to the outside, like the water pump. In this 2025 Porsche 911 Carrera GTS T-Hybrid guise, the new engine produces 478 hp and 420 lb-ft of torque by itself, and spins to 7,500 rpm. We’re eager to see what it can produce in future naturally aspirated, twin-turbo, and other versions.

Bigger Turbo, Too

A bigger turbo is another great way to enhance breathing, but enlarging both the engine and the turbo is a recipe for horrendous turbo lag. That’s where the T-Hybrid’s turbine motor comes in, quickly spooling up to 120,000-rpm, cramming air in at a relatively lofty 26 psi, and building to peak boost in 0.8 second, whereas the 3.0-liter’s smaller twin-turbos in the old 911 GTS needed almost three seconds.

The turbo features typical oil-cooled bearings with water-cooling of the housing and motor, complete with pumps that keep fluids flowing if the engine shuts down while the turbos are hot. According to Porsche, this single turbo and its manifolding weigh 59.5 pounds—same as the 3.0-liter’s two smaller turbos and their more compact manifolding.

27-Hp In, 15 Out

The electric turbo motor can draw as much as 20 kW (27 hp) when spooling up, but of course, running at such high rpm, torque is low, at 2.6 lb-ft. The good news is that at high engine speeds when there’s excess exhaust pressure, rather than blowing off a wastegate, the motor regenerates energy, drawing as much as 11 kW (15 hp) out and returning it to the battery (or to the electric motor if the battery’s full).

High-Voltage Battery

The 1.9-kWh battery operates at 400 volts, is about the size of a modern luxury car’s starter battery, weighs about 37 pounds, and is mounted directly over the front axle for ideal weight distribution. This battery supports high-draw loads such as the AC compressor, the Porsche Dynamic Chassis Control roll stabilizer, and the front-end lift mechanisms, speeding the actuation of both. There are no belt-driven accessories. A dedicated cooling circuit keeps the battery at about 100 degrees F (the powertrain circuit runs at twice that). Its cylindrical cells (measuring roughly 19 x 64 mm) are unlike any in Porsche’s E-Hybrid PHEV range. These are designed to work more like capacitors—able to quickly absorb and release energy. This battery starts the car via the e-motor attached to the engine (there is no separate starter). A lightweight 12-volt lithium-iron-phosphate battery mounted in the rear supports the low-voltage equipment and “wakes” the car before starting it.

Unique Traction Motor

The permanent-magnet assist electric motor is not directly related to those in Porsche’s existing E-Hybrid models and looks very different from typical electric-car motors. The rotor is nearly hollow, with permanent magnets lining its outer edge, unlike the V-formations used in typical EV rotors. Continuous output is 55 hp and 110 lb-ft, with 65 hp available in 10-second bursts. System output is 532 horsepower and 449 lb-ft. Achieving this same combined output with hybrid gear alone would have required a larger, heavier motor and battery. The T-Hybrid system is made for performance, yet consumption is also reduced slightly (WLTP combined consumption improves by 0.1 liter/100 km, which would equate to about a 1-percent mpg improvement). That’s impressive given the 18-percent increase in system power and the fact the combustion engine is 20 percent larger.

No Full Electric Mode

There is no clutch between the engine and motor, so the 2025 Porsche 911 Carrera GTS T-Hybrid has no pure-EV mode for sneaking silently around your neighborhood. There is still a dual-mass flywheel, and it gets quite a workout on an engine that lacks the momentum and balancing effects of a front-mounted harmonic damper or accessory drive, and which features crankshaft counterweights that are trimmed considerably as compared with those on the 3.0-liter’s crank.

A Packaging Miracle

Porsche 911 engine bays are always crowded, and this one looks like it required Tetris expertise to fit everything in. The dressed-engine height is lowered by 4.3 inches, freeing up room to mount the hybrid system’s power electronics. The jumbo e-turbo is packaged off to the passenger side, leaving room for the turbo plumbing, catalysts, and particle filters (standard in all markets now that there’s no power penalty) directly behind the engine. The big resonator/muffler fills the area to the left of the engine.

If our thrill ride around the company’s Weissach test track in Germany with pro racer Jörg Bergmeister—who established a Nürburgring lap time 8.7 seconds quicker than in the previous GTS—is any indication, 2025 Porsche 911 Carrera GTS T-Hybrid drivers will enthusiastically embrace this approach to electrifying their beloved rear-engine sports car.