Originally Posted by Mike@N54Tuning.com
There is no JB4 for the F30 yet. Only the N55 Stage1 tune. It does not leave codes behind but if you are worried they sell a complain tool called the "CAN Tool" that will delete hidden codes. Alternatively you can get the BT Tool which lets you read codes via laptop from all modules on the vehicle.
Gains are 40-50hp and well worth the 5 minute install time.
Thanks for the info, Mike! If you purchase the Stage1 tune are you able to upgrade it to the JB4 or whatever the next version is? When do you expect to have an actual JB4 for the F30 and will it come with a CAN tool?