Gen 2 3.5 EB w/ enabled flex fuel. Larger intercooler, larger lift pump, and larger port injectors to handle to load. Also have minor drop-in filter and cat-back upgrade. The truck is running well and I?ve finally got everything smooth on the tune for performance. I have not touched my timing yet. It seems that the ecoboost engines do not accept a lot of timing advance compared to most. I?m finding so many variations in the process and have some questions. Does the MBT actually change with E85? Some say that it actually needs to retard at low loads due to the burn rate while advancing up higher. Some say MBT is MBT and does not change. I?ve also read that with E85 I can pretty much copy the entire MBT to borderline as long and I disable other advance limits?but it seems pretty aggressive as a process to me. I understand how I can data log a run at WOT and find out which tables are needing modified but I would like a safe starting point and map point I can work from/too without the risk of damaging anything. The last census I heard was to advance a degree and when you start getting a gain of only about 1.5-2.5 torque increase?stop. But what if that exceeds MBT and does any stock tables need retarded just from the conversion? Thanks in advance for any help.