Description You wanted to get your feet wet with M-Engineering’s single file calibration but are now craving custom features and more power? Not to worry! M-Engineering can upgrade you from the M838T or M840T Single File Calibration to their feature packed M838T or M840T M-Tuner Calibration Suite at anytime! *M-Tuner requires a one time only bench procedure which requires the ECU to be sent to M-Engineering HQ. Disclaimer: You accept responsibility and risks of any tunes and added features by M Engineering. If you are not the end user of the car, you will be solely responsible for notifying the purchaser and/or customer they also accept the responsibility and risks of these and M Engineering is not liable. M Engineering is also not liable for voided warranties due to installation of these products.
