Volkswagen has revealed initial details about the 2,0-litre TDI engine that is set to be offered in the upcoming Golf 8.
The Wolfsburg-based firm says the diesel-powered version of the eighth-generation Golf will benefit from “the next evolutionary stage” of the brand’s selective catalytic reduction (SCR) system.
The updated system, which VW claims “significantly reduces nitrogen oxides in the exhaust gas”, is set to feature “twin dosing”. In effect, an aqueous reducing agent (Adblue) is injected selectively upstream of two SCR catalytic converters, which are arranged in series.
Already in use in the 110 kW Passat 2,0 TDI Evo offered in Europe, VW says the new system meets the technical requirements of the future Euro 6d emission standard. The new Golf, the automaker reveals, will feature twin dosing in all TDI variants.
VW claims “real driving emissions” measurements confirm nitrogen oxide levels are reduced by “around 80 percent” compared with the previous generation of the respective model.
The twin-dosing process requires a second SCR catalytic converter, which is located in the underbody of the vehicle. Since the distance to the engine is greater, VW says the exhaust temperature upstream of the second unit can be as much as 100°C lower.
“This expands the window for aftertreatment of exhaust gases: even at exhaust gas temperatures close to the engine of +500°C, the system is still able to achieve very high conversion rates. In addition, a blocking catalytic converter downstream of the SCR system prevents excess ammonia slip,” the firm said.
The new Golf is set to be fully revealed later in 2019, likely in October.