LEOPOLDSHOHE, Germany — Nissan's GT-R will deliver an estimated 550 horsepower when modified with Cobra Technology's Stage 1 upgrade, according to the German tuner. To achieve that increase, Cobra reprograms the engine computer, swaps new filters into the air intake and increases boost pressure by almost 2.2 psi.Cobra says this Stage 1 package, called the Cobra N+ Tuning Concept, will drop the GT-R's 0-to-60-mph time to less than 3.5 seconds, while top speed is up to 199 mph. The company is also working on a new stainless steel exhaust system for the GT-R. Those wanting more power will have to wait for Cobra's Race Performance package, which should make 620 hp and 590 pound-feet of torque.The Cobra N+ rides on lightweight 21-inch wheels and adjustable Cobra coil-overs. To aid in braking, discs have been upsized to 405 millimeters in the front with eight-piston calipers. Cobra also offers the full package of body upgrades, including front and rear apron, rocker panels and spoiler. The company claims that the new front airdam reduces lift and aids in cooling. Inside, Cobra offers custom upholstery in leather and Alcantara, carbon fiber racing seats, six-point seatbelts and a roll cage. The GT-R doesn't arrive in Europe until spring of 2009, at which time Cobra Technology will release its Stage 1 upgrade.Inside Line says: As the Nissan GT-R nears its European arrival, expect more tuners to pump out power packages to appease Godzilla. — Eric Tingwall, Correspondent