Kia has introduced a one-off track car. Developed by Kia engineers at the company’s Namyang development center in Korea, the Stinger GT420A is equipped with a 3,342cc V6 twin-turbocharged direct injection gasoline engine.
The HMETC powertrain team were involved from the start to tune the Stinger GT S track car, using HKS M45il spark plugs for enhanced combustion. A K&N sports air filter and a lightweight Milltek Sport quad-exit exhaust system with catalysts deleted were fitted in place of the factory item.
A six-row automatic transmission cooler is also fitted, in place of a four-row item, ensuring that the automatic transmission doesn’t overheat. The transmission software was recalibrated to have quicker shifting characteristic in Sport and Sport+ modes.
These measures bring the vital statistics up to 422bhp and 560Nm of torque, but any racer knows that lightness is key to making the most of this additional performance.
Kia also stripped out the interior of the Stinger, removing the seats and belts, airbags, sound system, interior trim and rear window regulators. The engine cover, undercovers, parking sensors, boot and bonnet dampers, and rear bumper beam and foam were also taken out, while the rear windows were glued into place and lightweight door cards installed.
The Stinger’s sunroof was removed and replaced with a steel panel, shaving off weight. There is a total weight reduction of approximately 150kg (330 lb) after the installation of the roll cage, seats, belts and fire extinguisher.
A custom roll cage was installed and painted and the crash pad and necessary electronics re-assembled. Underbody stiffening comprises of a cross bar at the front and a pair of bars at the rear. With the roll cage in place, a pair of Sparco race seats were bolted into place, along with race belts and the all-important fire extinguisher mounted within the cockpit, should the worst happen. Completing the weight saving measures, a Lite Blox lithium-ion polymer battery is installed to replace the original item, saving 22kg (48 lb).
The weight saving continues with the fitment of wider OZ Racing Leggera rims saving approximately 5kg (11 lb) per wheel, while Pirelli Trofeo R tires were selected for maximum adhesion on the track – 235/35/R19 at the front and 265/30/R19 at the rear.
The camber angle was increased to -2.5° though modification of the front cross-member, and uprated front brakes saw Brembo six-pot calipers and racing steel flex pipes fitted, along with high-performance 380 x 34mm discs and Endless pads.
At the rear, the standard Stinger V6 brakes were utilized. Cooling ducts and deflectors make sure that the brakes have the maximum cooling capacity needed on the racetrack and tweaks to the anti-lock brakes, traction control and electronic stability control ensures that they deliver optimum performance for on-track use.
The standard dampers were used for the racing setup, with Eibach Pro lowering springs and anti-roll bars of 25mm at the front. At the rear, a 17mm in-house anti-roll bar was fitted. The continuous damping control was axed in favor of a conventional damper setup with some fine-tuning.
Once the mechanical upgrades were signed off, a Stillen front splitter and rear diffuser were added, along with a rear spoiler by Air Design.