Did a good bit of searching through the numerous threads on this topic and got a lot of bits and pieces of very helpful information but couldn't find anything that addressed my question exactly. Apologize if I missed something and thanks in advance for pointing me int the right direction. Riding a 2011 FLHX with the 103 Power Pak. Already installed V&H big shots and the HD heavy breather. Still running great but only have about 500 miles right now. Am debating which fuel management strategy to go with and am on the fence with the Dobeck TFI. What bothers me is the Dobeck approach of bypassing the O2 sensors. I may be a bit dense but I am not getting the logic behind doing so. I could understand the benefit of the manual tuner before the O2 sensors were there. Seems to me that bypassing them would be discarding data that should support automatically making the tuning adjustments based on actual conditions. I am certainly no expert but have been reading about closed loop vs open loop. Am I missing something?