Spanish hot hatch loses 10bhp due to new emissions-testing regime.

The new Worldwide harmonised Light vehicle Testing Procedure (WLTP) testing regime has forced Seat to detune its Leon Cupra 300 and create the Cupra 290.

First reported by the UK's Auto Express, the company has confirmed the front-wheel drive versions of the Leon Cupra will lose 10 horsepower (7kW) to comply with new WLTP regulations (now 290bhp/216kW), though the all-wheel drive Leon Cupra ST wagon will maintain its 300hp (224kW) power output.

"In the context of new homologations, there are adaptions for the exhaust-gas-treatment and for the power output," a Seat spokesperson told Auto Express.

"From now on, all front wheel drive 2.0 TSI Cupra will feature a 290PS engine, while the 4-wheel drive will feature a 300PS engine."

It's unclear at this stage whether the front-wheel drive Cupra's performance and fuel economy figures will be affected by the changes – currently, the five-door hatch claims a 5.8-second 0-100km/h sprint and a CO2 emissions rating of 158g/km.

For the uninitiated, the Seat Leon is the Spanish brand's version of the Volkswagen Golf, sharing the German hatchback's MQB underpinnings and various powertrain options – though it isn't offered in Australia.

In Cupra spec, the Leon utilises the Golf R's high-output 2.0-litre turbo petrol engine, though it sends drive exclusively to the front wheels in three- and five-door hatchback forms. The Leon ST Cupra wagon offers the option of all-wheel drive, meanwhile, making for a claimed 0-100km/h time of just 4.9 seconds.


What is WLTP?

WLTP serves as a replacement for the New European Drive Cycle (NEDC), which was developed in the 1980s and has been in use throughout Europe since 1996.

Developed with heavy input from European automakers, WLTP uses data about driving styles and is designed to better reflect real world situations.

Compared to the NEDC, the WLTP cycle runs for a longer period: 30 minutes compared to 20 minutes. The cycle distance is also significantly longer at 23.25 kilometres, compared to 11km for NEDC. Shift points are also now calculated on a per-vehicle basis.

During a normal cycle, a car goes through laboratory tests mimicking low, medium, high and very high speed driving situations with stopping, acceleration and braking. Mathematical models will be used to calculate differences in fuel economy for low and high spec trim levels.

As it is a bench-testing regime with strictly defined parameters, WLTP still doesn’t take into account common variables, such as aerodynamics and operation in different climates, but it does include mathematical adjustments for optional equipment.

New models introduced in Europe from the beginning of September 2017 are required to be tested under the new WLTP regime, with all vehicle registrations from September 2018 required to have a WLTP rating, although there are some exceptions for unsold cars reaching the end of their product cycle.

Despite its name, WLTP is only legally required for cars being sold within the EU for now. WLTP figures will not only be used for informational purposes to aid comparative shopping and calculating corporate fuel economy numbers, but, depending on the jurisdiction, can also be used to determine sales tax, annual road taxes, and registration classes.

If WLTP is adopted by countries outside of the EU, there is leeway for them to modify the test procedure to account for different driving styles, and road and atmospheric conditions.