Asking the community for some info. I have a 2018 ZL1 (LT4). Running E-85. I just replaced the high side factory pump with Lingenfelter's Big Bore pump. My understanding is that Lingenfelter actually uses an LT1 pump and runs a bigger bore. They also state very clearly that the maximum operating pressure should not exceed 2,175 psi just like the LT1 stock pumps. So I have all the of that in the revised tune. Basically, I have an LT1 pump tune profile instead of my stock LT4 tune. Ever since I swapped the pump I now run lean in both banks and end up with a fuel rail pressure too low during engine cranking. These are showing up as DTCs with a lit CEL.
I've contacted Lingenfelter but can't get them to respond. Anyone know what changes need to be made to the tune for their pump?