All of Ferrari's previous XX models were solely for the track, but that has changed with the newly unveiled SF90 XX Stradale and SF90 XX Spider convertible. Customers can enjoy these more powerful models on public roads. However, Ferrari keeps them rare by making just 799 hardtops and 599 droptops.

Both models continue to use a twin-turbo 4.0-liter V8 with assistance from three electric motors – two for the front axle and one between the engine and transmission. The power output grows to a total of 1,016 horsepower, versus 986 hp for the standard SF90 Stradale.

By itself, the V8 in the SF90 XX Stradale makes 786 horsepower (586 kilowatts) instead of 769 horsepower (573 kW) for the previous iteration. The engine features new pistons, specific machining of the combustion chamber, and polished inlet and exhaust ducts. The tube coming intake plenum is closer to the cabin bulkhead to bring more of the engine's sound into the cabin. The engineers also eliminated the secondary air system to shed 7.72 pounds (3.5 kilograms). 

The electric motors also receive a power upgrade to make a total of 229 hp (171 kW) versus 217 hp (162 kW) for the previous iteration. The battery capacity remains at 7.9 kilowatt-hours. When running solely on electric power, the range is still 15.53 miles (25 kilometers), and the top speed in EV mode is unchanged at 84 mph (135 kph).

There's a new extra boost function from the electric motors when the SF90 XX is in the Qualifying driving mode. The system adds more power when exiting a corner, and Ferrari claims the feature cuts lap times around the Fiorano circuit by 0.25 seconds. The battery has enough juice to provide up to 30 of these power jolts.

The gearbox is still an eight-speed dual-clutch unit. Revised software adds a noise when changing gears that is similar to the exhaust note when lifting off the throttle at high revs.

Both models reach 100 kph in 2.3 seconds and have a top speed of 320 kph.

The SF90 XX Stradale has improved braking from redesigned front calipers with better cooling. The rear rotors grow to 390 millimeters instead of the existing 360 mm. A new ABS EVO controller works with the 6W-CDS sensor to get an estimation of the vehicle's speed and then calculate the proper braking distribution.

Ferrari tweaks the SF90 XX Stradale to look more aggressive than the standard model (see comparison above). A larger front splitter directs air under the car to channel the flow to the redesigned underbody. The automaker reports it produces over 45 kg more at 250 mph (400 kph) than the regular model.

Where the existing vehicle has a wide outlet on the hood, Ferrari adds more sophisticated aero elements to the SF90 XX. A pair of ducts are on each side of the nose, and there are two more near the center. Three gills are on each front fender.

The rear end receives equal attention. Two inlets are on the engine cover just behind the roof. There are also revisions to the openings in the fenders, and three gills are right behind them.

At the very back, Ferrari installs a fixed wing. The brand says this is the first road-legal model since the F50 to have one as standard from the factory. In total, the body revisions make 1,168 pounds (530 kilograms) of downforce at 250 kph.

Interior changes are more minor. The SF90 XX has an Alcantara dashboard and lots of carbon-fiber trim. The gearshift selector is farther forward. The seats appear to be a single-piece design, but elastic trim connects the upper and lower sections so occupants can adjust the backrest.

The SF90 XX Spider is largely similar to the SF90 XX Stradale, except its roof can open in 14 seconds. The revisions for the droptop mean that some of the inlets in the rear deck of the coupe are gone.

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