The Porsche 911 Targa has been given a facelift and gets a healthy dose of mechanical upgrades.

Two versions will be available: the Porsche 911 Targa 4 and 911 Targa 4S, both with four-wheel-drive.

While the Porsche 911 Targa 4 gets its power from Porsche’s 3.6-litre engine (now producing 345bhp), the Targa 4S has a 3.8-litre flat-six developing 385bhp.

View more pictures of the facelifted Porsche 911 Targa

Both engines have been thoroughly re-designed over the previous model and now feature direct fuel injection which increases power by more than eight per cent and reduces fuel consumption by more than ten per cent.

The Porsche 911 Targa 4 accelerates from 0-62mph (100km/h) in 5.2 seconds and has a top speed of 176mph while the Porsche 911 Targa 4S stops the clock at 4.9 seconds and rushes on to 185mph.

Other big news is the inclusion of Porsche’s PDK gearbox, which has just debuted on the facelifted Porsche 911 Coupe.

View our exclusive spy shots of the facelifted Porsche 911

It’s Porsche’s take on the dual clutch gearbox with Formula 1 style gear change buttons on the steering wheel.

Gear changes are almost instant and a Porsche 911 Targa fitted with PDK (a £2,338 option) is claimed to be 0.2 seconds faster from 0-62mph than a manual car.

The Targa has a 1.54-square metre glass roof made of two sections: a top piece and a rear tailgate.

When fully opened the top section slides beneath the rear tailgate in seven seconds, providing an open area of 0.45-square metres over the occupants.

Inside, the Porsche’s centre console is now compatible with Bluetooth communications and can connect with USB and iPod devices.

Both models of Porsche 911 Targa go on sale on October 25 with the Targa 4 priced from £72,980 and the Targa 4S priced from £80,270.

Check out this video of the awesome Porsche 911 GT2: