Prior to this development, BMW N54 enthusiasts were limited to the extent they could blend E85 with regular gasoline and still have the engine operate safely within the window that the ECU fuel trims could accommodate. By giving end-users and professional tuners the ability to manipulate fuel scalars on their own, this limitation has been removed, allowing the ECU to operate with alternate fuels in the same way it does with traditional gasoline and maintain fuel trims within a range of 1%-3% while producing impressive power gains with excellent power delivery characteristics.
A Fuel Scalar table is assigned to each cylinder bank in the AccessTUNER software. For most ECU’s, these tables are simple one-dimensional scaling factors that allow the user to adjust the fuel scaling up or down as needed. In the 1M ECU, the fuel scalar tables are two-dimensional 16×16 tables that scale fuel based on engine RPM and load.
Due to variation in fuel blends across the country, E85 Off-The-Shelf maps will not be available for download. Instead, the end-user is empowered to tune specifically for the fuel blend at their favorite fuel source using AccessTUNER software and data-logging to ensure proper performance. This also allows the end-user to blend different fuels to their liking and quickly tune for it. The BMW AccessTUNER Help Guide has been updated to include Fuel Scalar table descriptions as well as a reference chart for estimated Fuel Scalar values for different blends of ethanol and gasoline.
To update AccessTUNER and acquire the latest Fuel Scalar tables, simply open the software, click on Help in the menu bar, select Updates and click Check for Updates. In the pop-up window, check the Beta Software box in the lower right corner. Click the Get Updates button and follow on-screen instructions to complete the software upgrade and start tuning for alternate fuels!
AccessTUNER Pro: 220.127.116.11-4419
AccessTUNER Race: 18.104.22.168-4414