Originally Posted by ign335i
This is not true. You can do 100% E85 with BMS flash and a JB4 without an upgraded fuel pump. With FBO and larger turbos you will need upgraded fuel pump. The pump is at its limits with stock turbos and 100% E85, but it can still do it in most cases without lean outs as I understand it. If you need upgraded pump you can source a Walbro E85 pump for $180 plus $20 of fittings and that solves the LPFP issue. There is a DIY out.
I think the Walbro was a good aftermarket solution if your LPFP was actually failing, but I think they found that pump alone was still dropping pressure because it couldn't maintain the surge volume required at peak torque.