Click above for a high-res gallery of the 2008 Porsche 911 GT2.

Porsche's commitment to the KISS philosophy of exterior design won't extend to the engine of the facelifted 911 Turbo, GT2 and GT3 when they're released early next year. All three models will dispatch with the legendary M97 powerplant in favor of the new, direct-injected A91 flat-six that's equipped on the recently updated 911 Carrera.

The two turbocharged 911s will be packing 3.6-liters of displacement, with a 97 mm bore and an 81.5 mm stroke (the outgoing engine was sized 100 mm x 76.4 mm), along with revised turbochargers and intercoolers. Autocar's sources suggest that output on both models will rise by around 20 hp, with the Turbo producing 500 hp and the GT2 pushing out approximately 550 hp. Torque figures should also increase by around four percent.

The GT3 will remain naturally aspirated, with a 3.8-liter version of the A91 with a 102 mm bore and a 77.5 mm stroke. The same internal changes from the Carrera S will carry over to the GT3, including lightweight pistons, valves and springs. Output should increase from around 415 to 430 hp. And all of these changes will also increase fuel efficiency and decrease C02 output. 'Cause that's what really matters... right?

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[Source: Autocar]