Porsche has unveiled an updated version of its 911 GT3 RSR racecar, which will participate in next year’s GT Championship. The German firm's engineers modified the exhaust system and air intake housing, with the 4.0-liter boxer powerplant delivering 5 more horsepower, for a total of 455 hp at 7,800 rpm. While the power increase isn't much of an improvement, Porsche claims that the six-cylinder unit is better adapted to different fuel grades and its driveability is superior compared to the outgoing model. Read more »