User-choosers will have until the end of July – or while stocks last – to take advantage of the offer, which Subaru claims is worth £1,995 for the STi and £1,600 on the WRX.
The Prodrive-developed Performance Packs are fitted by the dealer after registration and carry the full Subaru three- year/60,000-mile warranty.
It means the Impreza WRX STi Type-UK has a 0-60mph time of 4.6 seconds. Top speed is in excess of 155 mph. The standard WRX’s 0-60 mph time is reduced from 5.6 seconds to 4.8 seconds. Both Prodrive Performance Packs include a reprogrammed Electronic Control Unit (ECU) and free-flow exhaust system with a large single rear tailpipe.
The Impreza WRX saloon costs £20,300, with the five-door at £20,800, while the WRX STi Type-UK is £26,400 (all prices on-the-road).