The N54 twin turbo BMW 335I is one of the best platforms to modify and with a simple ECU upgrade, the car becomes a whole new animal. Our ECU Flash is a actual ECU upgrade, not a piggyback. So we are adjusting the parameters on the ECU. With our system it is all done via the OBDII port which means you can flash it at your convenience. You can revert to your stock file for warranty purposes and it is undetectable by dealers. As tested on other N54 cars, we have seen a gain of 65 rear wheel horsepower and 70 ft/lbs of torque! Order your BMW 335I ECU Upgrade here. Leave a Reply Cancel ReplyYou must be logged in to post a comment.