I had the JCW kit installed on my CooperS/184PS about 3weeks ago. At the same time, the thermostat for the cooling circuit gave up my mind and had to be renewed. The first two days I had the feeling that the kit was getting right from the bottom out. However, the feeling had faded relatively soon and it feels like everything was back to the old age. In addition, the car is now in the upper speed range felt tougher than before. With 205/45/17 tyres reached (GPS 228/229) Now with JCW Kit and 195/55/16 tyres is really on straight track at 238/239 end. (GPS 225/226). I’m pretty fucked up now because are registered with JCW Kit 235km/h and that would be like 248/249 after Tacho. That’s not to be thought of. How much do your Cooper S run with 184ps/with JCW Kit to Digitaltacho on straight track if possible with tail wind(how much normal without waiting forever) I assume that a product that costs 2000.- and promises more performance also has to bring more performance! How can I successfully claim this at BMW!