I am currently running an SD tune on my c5 ls1. I spent the last week tuning my VE table...hitting as many cells as possible in as steady state as I could get on the street. I tuned this using a VE Lambda error histogram...I did a conversion in hptuners to display my dynojet wideband in units of Lambda. Yes I had my trims and fuel cutoff disabled . I got everything dialed in very nicely...between .99-1.01 and I verified that across different days and weather patterns..it is rock solid according to my wideband and the car runs VERY smooth. No bucking...I can cruise control at 900 rpms in 6th...the cam is a 227/235.
So today I turned back on my STFTs (I don't use LTFTs) and they were off as high as -12% in some areas! So I figured, ok maybe my lambda calculation was off...so I did another log just logging raw AFR values (again with STFTs off) and every cell I hit was hovering around 14.7 AFR, so I was just about dead on. With the STFTs turned back on, my AFR was consisently in the mid 15s!
A week ago, before I began tuning, I did get the 02 heater codes on both banks, but the code cleared itself and never came back a day later. Could my 02s just be on the way out or is this normal behavior for having headers and a cam? I see people like to run the corvette rear 02 sensors and run an adapter. Could that be my solution? Or should I just run OLSD?