I put an 06 Z06 Road Course car up on the dyno to do a quick baseline and check A/F's. The car is pulling a bunch of timing with SEMRET. The curious thing is this car worked really well. It was tuned by the crew that built the engine a few years ago. The changes that have happened are a diff change, valve spring change and some mild cleanup in the ports (nothing real serious).
I have read alot of the threads regarding this however find nothing real conclusive to help. B2514 is maxed and B2517 is maxed in forward gears.
Attached are some recent logs.
Jay_06_zo6_02.efiJay_06_zo6_03.efiJay_06_zo6.efiJay_06_zo6_04.efi
What could be causing this reduction? Is there hardware that could be malfunctioning and causing this?