HORI, Switzerland — Sportec, the Swiss Porsche specialist, has introduced the SP750, its range-topping performance upgrade for the Porsche 911 GT2. In fact, Sportec offers several stages of tune for the GT2.The SP750 is so-called because Sportec's kit for the twin-turbo 3.6-liter flat-6 engine kicks output to 750 PS, or 740 horsepower, with torque climbing to 627 pound-feet.Sportec has reprogrammed the ECU and fitted more potent turbochargers and larger intercoolers, along with other internal engine mods, including titanium connecting rods and sport cams. A high-performance exhaust system includes high-flow catalytic converters and twin tailpipes. The company claims 0-60 acceleration takes less than 3.2 seconds, while top speed jumps to 217 mph.The SP750 also gets a reinforced clutch kit and rides on Sportec SPR alloy wheels, available in polished or anthracite finishes, with Michelin Pilot Sport tires — 245/30ZR20 front, 325/25ZR20 rear.Additional hardware enhancements include upgraded suspension and brakes, as well as revised aerodynamic bits. An aluminum pedal set, velour floor mats and a choice of leather or Alcantara upholstery and trim are among the interior appointments.If that's just too much oomph, you can start with a Phase 1 upgrade: 599 hp and 586 lb-ft, with 0-60 acceleration in less than 3.5 seconds and a top speed of 210 mph. The next Phase kit will kick things up to 646 hp and 586 lb-ft, with the 0-60 sprint dropping to less than 3.3 seconds and top speed swelling to 214 mph.What this means to you: Not quite the fastest street-legal Porsche out there, but pretty darn quick. — Paul Lienert, Correspondent