Ferrari’s FXX model designation has become a long-lived series, with new variations appearing in the track-car marketplace with increasing frequency. The 2005 FXX was followed ten years later by the FXX K. And, about a week ago, the company revealed its newest track-only model designed especially for enthusiasts, the FXX K Evo.

The original FXX was loaded with the cachet of secrecy; Ferrari guarded tech and aero features closely, as they overlapped with key elements of the company’s F1 designs. Only 30 were built. The 40-example FXX K followed in 2015, with updates including the Kinetic Energy Recovery System borrowed from the now-legendary LaFerrari.

According to Ferrari, this latest FXX represents the natural evolution of the design—hence the ‘Evo’ in the name—and continues to refine, most notably through a dramatic increase in downforce. The KERS is still onboard, too, making it a mild hybrid design.

The last FXX K presented amateur track drivers with a buying option that sported one of the best aero packages in that class, and the Evo takes things even further; Ferrari apparently spent a year tweaking the design using CFD and tunnel testing, and came up with improvements including a new rear wing, a redesigned bypass vent, and adjustments to the bumper designs. When all is said and done, the Evo manages a better than 20% increase in downforce over the K. But, current K owners can take advantage of Ferrari’s year in the lab, and have their car upgraded to Evo specs.

The LaFerrari drivetrain remains intact, with the 6.3L V12 pushing 1,035 horsepower, and a seven-speed dual-clutch gearbox delivering the juice. And, as for the car’s weight? Ferrari will only say that it’s lighter. But the K tips the scales at just over 2,500 pounds, so the weight loss represented by the Evo can’t be extraordinary.

Production numbers are still a mystery, too, but less than 50 is a safe bet. The FXX K Evo will begin appearing next year.