According to Britain's Autocar Magazine, the GTI will most likely retain the stalwart 2.0-litre TSI engine, but with the addition of a 48 volt electrical system and integrated starter motor as part of an extensive powertrain overhaul.
It also claims that the modifications would result in the exhaust gas turbocharger making way for an electric compressor that will provide a better distribution of torque, while the integrated starter will act as a sort of boost option by mounting the electric motor in the front half of the seven-speed DSG gearbox when in Performance mode.
Elsewhere, cooking version of the Mark VIII, which goes on sale in 2019, will use an updated version of Volkswagen MQB-platform, rumoured to cut weight by 50 kg compared to the current Mark VII, with engines expected to a include a new 1.0 TSI in place of the current 1.2 TSI, a 1.5 TSI replacing the old 1.4 TSI and a new 1.5 TDI instead of the 1.6 TDI.
The latter petrol engine will come as standard with cylinder deactivation and coasting function in BlueMotion guise, helping lower emissions to a claimed 104 g/km. A revised six-speed manual gearbox or seven-speed DSG box will once again be offered, while 4Motion four-wheel drive will be available in a number of select markets.