Subaru decided to sweeten up its deal for the Impreza WRX STI by offering a power upgrade and a sat nav at no extra cost to its customers in the UK.
The 2.5-litre 16-valve turbo engine powering the Subaru WRX STI develops 300 PS and 407 Nm of torque, but for those who are interested in purchasing one of these models by the end of June, the Japanese automaker will offer a free engine upgrade which will enable an additional 20 PS and 43 Nm of torque.
This will enable quicker acceleration times (0 to 62 mph in 4.9 seconds) plus the car will also be equipped with a Pioneer sat nav as standard, which features a detachable touch screen display and offers Bluetooth and iPod connectivity.
The Subaru Impreza WRX STI price for UK remains at 32,995 GBP and the offer mentioned above applies to both 4- and 5-door versions.
Subaru press release :
    * Engine upgrade to 320 PS
    * Improved torque and driveability
    * 0 to 60mph in under 5 seconds
    * Sat nav fitted as standard
Spring is in the air for Subaru customers with the company’s latest generous offer on the iconic high-performance STI. A by-word for exceptional real world driving performance, the characterful STI is now available with upgraded engine power and a satellite navigation system as standard and with no increase to the OTR price of £32,995 − but for a limited period only.
The already widely praised, revised 2.5 litre Subaru Boxer 16-valve turbo engine produces an already impressive 300 PS at 6000 rpm and 407 Nm at 4000 rpm in standard trim. Customers who purchase an STI between now and the end of June will get an engine upgrade which will result in an extra 20 PS and even more mid-range torque, leading to final performance figures of 450 Nm at 3400 rpm.
The power pack has been developed in-house at Subaru UK and is covered by a Subaru UK warranty. A sub five second sprint to 62 mph puts the STI firmly in the supercar category, despatched in just 4.9 seconds. 
In addition to the significant engine enhancements, STI’s purchased in the qualifying period will also get a Pioneer sat nav fitted as standard. The system features touch-screen capability, Bluetooth and iPod connection. The screen is also detachable and can be connected to a laptop via a USB port for easy downloading of additional information.
All STI’s come as standard with symmetrical AWD, keyless entry and push button start, hill start assist, climate control, SI-Drive, leather Recaro seats, 18 inch alloy wheels, remote locking, satellite tracker and cruise control.
The STI offer runs from April 1 until June 31 and applies to both 4 and 5 door variants. 

Source: Subaru