M-Engineering Calibration Suite upgrade Senna The OEM spark plugs use

The OEM spark plugs use a 14mm head

This is the a genuine McLaren transmission filter

These spark plugs are one step colder

McLaren SENNA - Calibration Notes

Let your engine breathe a little better while still filtering down to 4-5 micron per ISO5001 filtration standards

M-Engineering Calibration Suite upgrade Senna The OEM spark plugs useYou wanted to get your feet wet with our single file calibration but are now craving custom features and more power? Not to worry! We can upgrade you from the M838T or M840T Single File Calibration to our 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