The Evolution VI's development focused primarily on cooling capacity and engine durability compared to its predecessor. The car received a larger intercooler, a larger oil cooler, and new pistons. Most significantly, the RS model became the first production car to use a titanium-aluminide turbine wheel, a material chosen for its low inertia and heat resistance that allowed faster turbocharger spool-up. The official power output remained at 280 PS at 6,500 rpm, the ceiling established by a gentlemen's agreement among Japanese car manufacturers, with maximum torque quoted at 373 Nm at 3,000 rpm. The exterior received another revision, with the front bumper seeing the most noticeable change: the large fog lights were reduced in size and repositioned to the corners to improve airflow. The standard GSR and RS trim levels were joined by a new RS2 variant that combined the RS base specification with selected GSR options.
Released in December 1999, the Tommi Mäkinen Edition was a limited-production special variant of the Evolution VI produced to honour Mäkinen's four WRC Drivers' Championships for Mitsubishi. Total production of this edition was 4,092 units. Compared with the standard Evolution VI, the Tommi Mäkinen Edition featured a revised front bumper design, Red and Black Recaro seats with an embossed Mäkinen logo, 17-inch white Enkei wheels, a leather Momo steering wheel and shift knob, a titanium turbine for quicker spool-up, a front upper strut brace, lowered ride height optimised for tarmac stages, and a quicker steering ratio. The edition was offered in several exterior colours, with red available exclusively in this variant, and optional decals could replicate Mäkinen's rally car colour scheme. The Tommi Mäkinen Edition is sometimes referred to by collectors and enthusiasts as the Evolution 6.5 or TME.
Mitsubishi's WRC success with the Lancer Evolution reached its peak across the period spanning the Evolution III through Evolution VI. Tommi Mäkinen secured Drivers' Championships in four consecutive seasons from 1996 to 1999, driving Evolutions III, IV, V, and VI in turn. In 1998, Mäkinen and teammate Richard Burns together delivered Mitsubishi its only WRC Constructors' Championship. The Evolution VI contributed the final championship in that sequence, with Mäkinen winning the 1999 Drivers' title. Mitsubishi continued to campaign the Evolution VI under Group A regulations into the early part of the 2001 season before transitioning to World Rally Car rules with the Evolution VII. The FIA's requirement that all top-level WRC competitors use the World Rally Car regulations from 2001 effectively ended the Group A era for Mitsubishi.
Alongside the Tommi Mäkinen Edition, Ralliart in the United Kingdom produced a limited RS Sprint variant tuned for lighter weight and higher power output of 330 hp. The standard range comprised the GSR as the higher-equipment road-oriented model and the RS as the lightweight competition-biased variant with a close-ratio five-speed transmission. The Tommi Mäkinen Edition GSR added its distinctive specification over the standard GSR base, while the Tommi Mäkinen Edition RS version retained the close-ratio transmission and lowered ride height from the standard RS alongside the edition's specific front bumper and titanium turbine.
The Evolution VI sits at the end of a remarkable competitive sequence for Mitsubishi, marking the last year in which the company won the WRC Drivers' Championship. The titanium-aluminide turbine wheel introduced on the RS model was a genuine engineering first for a production car. The Tommi Mäkinen Edition became one of the most sought-after Evolution variants among collectors, and the association between Mäkinen's four titles and the Evolution lineage cemented the car's status in the history of Japanese performance cars.