We hit the track in Kia’s Stinger GT420
Take a Kia Stinger, add lightness and some extra power, and you get the Stinger GT420, a track car that highlights its maker’s passion for building sporty models
A FEW years ago, Auto Express drove an early prototype of a Kia designed to take on BMW and Audi at its own game in the sports saloon market: the Stinger GT S. According to Kia’s head of research and development, Albert Biermann (poached from BMW, incidentally), it was a car “that needed to surprise people” – and it did just that. It showed Kias could be fun.
Fast forward a few years, and the car that helped change perceptions of the Korean brand has received another injection of life. The Kia Stinger GT420 is a one-off track car created by Kia UK with help from sister company Hyundai and its European Technical Centre in Germany.
The story starts with that early prototype – the car that covered more than 10,000 development miles, with Biermann signing off the final calibration here in the UK on this very vehicle. Regulations state that pre-production cars have to be crushed when they’re finished with, but Kia claims it’s bent those rules, “an unfortunate and mysterious delay in creating the required paperwork” the reason for the GT420’s existence.
It’s a project that’s proved the passion for performance vehicles within Kia, and once the firm had sidestepped the regs, the skunkworks-style development team – led by Tyrone Johnson, previously of fast Ford fame – set to work on modifying the standard Stinger.
In the transformation to GT420, there’s been plenty of changes. The 3.3-litre twin-turbo V6 engine’s output was increased from 365bhp and 510Nm to 422bhp and 560Nm. That extra 57bhp and 50Nm of torque was liberated by two new K&N air filters, a lightweight Milltek Sport exhaust system with no cats, and a full remap, along with new HKS spark plugs for improved combustion. The team also fitted a bigger oil cooler for the car’s sixspeed automatic transmission, which was recalibrated to give faster shifts in Sport and Sport+ modes.
The interior was stripped of pretty much all its trim – only the upper dashboard remains – with the electronic controls for the driver modes and the gearlever grafted onto the Stinger’s bare skeleton. Even though a big roll cage was bolted in for safety, the GT420 is still 150kg lighter than the standard car, with a clever and supersmall battery helping save a whopping 22kg of that total.
The weight reductions were helped by the 19-inch OZ Racing wheels, which save 5kg per corner, and are wrapped in sticky Pirelli Trofeo R tyres. They cover big six-pot Brembo brakes at the front.
Kia’s team junked the electronically adjustable suspension in favour of a passive set-up – partly due to the limited timeframe they had to complete the car, and partly due to the limited budget – opting for passive Mando dampers tuned to suit the car’s set-up, and paired with Eibach lowering springs.
A bigger 25mm front anti-roll bar was added, while a 17mm anti-roll bar from a diesel Stinger was fitted at the rear to reduce the oversteer, because the car was very lairy in the development stages, according to the
The Stinger needed to surprise people, and it did just that, proving Kias could be fun
ALBERT BIERMANN Head of R&D, Kia