Since the flash tune program's inception in 1996, the one requirement was that the tune needed to be installed at a Dinan authorized dealer. This forced those in the international market or those in rural areas away from our core markets to either send in their DME for a bench flash or to simply live without Dinan tuning. No one should miss out on the chance to experience a Dinan tuned BMW so for those not near an authorized Dinan dealer a solution to tune your BMW is finally available in an easy to use DIY package. Complete with the various interface cabling that is needed for the vehicle the kit enables the end-user to be able to flash their own vehicle in the comfort of their own garage. The kit will also allow the user to flash the vehicle between stock and Dinan at a moment's notice whenever the need may arise. NOTE(S): 1. When ordering please ensure you have your VIN ready for the checkout process. It is crucial that it is typed in accurately and completely at that time. While we offer the DIY kits in Stage 1 form the additional stages will need to be purchased and installed at an authorized dealer as they require hard parts to function properly. 2. DIY software is at your own risk. Dinan is not responsible for any expenses incurred due to a failed flash. Please be aware of reccommendations for programming as referenced on page 8 of the installation manual (linked below) for optimum success. The programming cable does not have a recovery service and will require ISTA or similar BMW dealer tools in the event the ECU needs to be recovered. Software Description: After many hours of further research, tuning, and testing we have improved on our hugely popular Stage 1 Performance Software. Our team was able to make Stage 2 much faster by improving turbo response across the power-band. This tuning is especially noticeable in the first two gears, now catapulting the car off the line. Tuned for a smooth power-band to put down predictable and even power in all gears and throttle positions. This smoothness improves the quality of the shifting and the overall drivability. From a standing start (with the traction control fully disengaged) all it takes is the press of the throttle to the floor to get the tires spinning. The everyday practicality of a full-size sedan with the fun of a sports car, this is the definition of "Performance Without Sacrifice". With Dinan's software, your 550i will be capable of achieving its natural top speed as the governor has been removed. And as always, Dinan matches the new car warranty coverage for up to 4 years or 50,000 miles, including the possibility of consequential damages. No one offers better performance or backs it up with such comprehensive warranty coverage.