Car was tuned at sportec at stage 2 (almost), no internal improvements. It has carbon airbox, improved turbos (base on stock ones with reworked intake, output etc), new intake tubing and stock exhaust with racing cats. The biggest gain though came from the fact that the engine was opened up by sportec because of a typical problem with 996tts (loose intemediate shaft screw) and then put back together. In that process they had the chance to correct a lot of the mistakes that the factory has made in this engine that restrict power. The gain was 30-40hp just by opening up, cleaning the engine, correcting those mistakes and putting back together. Two of the most important mistakes were regarding the intake cam (off by almost 1 degree on most 996tt from factory) as well as some of the turbo tubing that have wide diameter on the sides but are narrow in the middle section! Apparently porsche wanted to use the same part for the tiptronic where there is restriction of space..! The last 2 "improvements" had as a result the engine to produce more and more power until 7,000rpm+ instead of up to 6,000rpm of the stock engine. So all of the above yield 540hp and 850nm of torque.