The Evolution VI shares the CP9A platform with the Evolution V, which had introduced the wider body and 17-inch wheels that distinguished the fifth and sixth generations from their predecessors. The focus for the Evolution VI was aerodynamic efficiency and engine durability, partly in response to changes in WRC regulations. The bi-plane rear wing replaced the single-plane unit, improving high-speed stability. Cooling was enhanced with a larger intercooler and larger oil cooler, and the RS model received the world's first titanium-aluminide turbine wheel in a production car, reducing turbo lag. The chassis received additional spot welds to increase rigidity and the suspension received detailed revisions.
A total of approximately 12,000 examples of the Evolution VI were built across all variants, including convertibles and special editions.
The 2.0-litre 4G63T turbocharged DOHC inline-four engine was rated at 280 PS (206 kW; 276 hp) at 6,500 rpm, held at the ceiling of the voluntary agreement among Japanese manufacturers which limited published power to 276 hp. Torque was 373 N·m (275 lb-ft) at 3,000 rpm. The drivetrain used a five-speed close-ratio manual gearbox and Mitsubishi's full-time AWD system with Active Yaw Control (AYC), which used computer-controlled hydraulics to vary torque split between the rear wheels and reduce understeer. Brembo disc brakes measuring 322 mm front and 302 mm rear provided stopping power. Wheelbase was 2,510 mm, length 4,350 mm, width 1,770 mm, height 1,405–1,415 mm, and kerb weight 1,260–1,360 kg on 225/45R17 tyres.
Performance as tested by Autocar in 1999, covering one of the first UK-market cars, was 0–60 mph in 4.4 seconds and 0–100 mph in 11.2 seconds.
The Evolution VI brought Mäkinen his fourth consecutive WRC drivers' championship in 1999, capping a remarkable run that began with the Evolution III in 1996. A commemorative limited edition, the Tommi Mäkinen Edition, was released in January 2000. It featured a revised titanium turbine tuned for better low-end response, lowered ride height of 10 mm, larger-diameter exhaust, improved oil pan, a new air dam, Red/Black Recaro seats with the Mäkinen logo, 17-inch white Enkei wheels, and a leather Momo steering wheel. Approximately 4,092 units of the Tommi Mäkinen Edition were produced. This variant is sometimes referred to as the Evolution 6.5 or TME.
While earlier Evolution generations were sold only in Japan, the Evolution VI was officially exported to the UK in small numbers, the first formal Western-market availability of the model. Following the 1999 championship, WRC regulations shifted toward more specialised WRC-specification machines, reducing the relevance of the Group A homologation programme to road car development. The Evolution VI is therefore considered the last of the pure Group A-heritage Evolutions.
The Evolution VI sits at the junction between the compact CE9A-platform Evos (IV, V, VI) and the larger Lancer Cedia-based Evolution VII that followed in 2001. The 4G63T engine ran through the Evolution IX; the Evolution X moved to the all-new aluminium 4B11T. The lightweight and comparatively underpowered nature of the Evo VI relative to subsequent generations — combined with the Autocar assessment that it could match Ferraris in a straight line and out-corner a Lotus — contributed to its reputation as the best of the breed among many enthusiasts.