Hello everyone. I'm working on getting my wife's 2006 GTO tuned, and it's been giving me a fair amount of grief. I've been doing a lot of reading on here with things such as EOIT and dealing with low speed stumbling issues as I didn't want to actually post up unless I felt I had to. Let's start with the car; it's a 2006 GTO M6.
LS3 swap
GM CNC'd LS3 heads
6.2L Flex fuel injectors (used, came from my Escalade)
Comp Cams 281LR cam (the cam is installed 3 degrees retarded)
Cadillac racing lifters
Lunati dual springs
Comp 7.400" pushrods
Kooks 1 3/4" longtubes with catted-y
I am trying to get the VE dialed in. I'm tuning in open loop until I have my trims close. I've tried a couple of the EOIT calcs, which helped a lot with the low end stuff (feels more response from idle to 2500 or so) but it will still start surging in the parking lot (which to be honest I don't care about at the moment) The main problem/concern I have been having is that somewhere about the 4000 RPM area, it will start breaking up/stuttering. WB02 values look good, not seeing any knock. The spark plugs I have in there are for an LS3 (Camaro, I believe) gapped to .034" if I remember correctly. I checked the fuel pressure at the rail, I see ~60 psi. After that, I upgraded the intank fuel pump to a DW300C and replaced the in-tank filter when I did so (it was gross) but saw no perceivable change.) The injectors do have mileage on them, but I'm not sure if that would necessary affect what I am dealing with as they ordinarily work fine, and I'm not seeing knock. I also changed to have 14.1 AFR for stoich instead of 14.7.
As I tend to log on my drive to and from work, and the logs can get long, I've cut out the relevant WOT part and uploaded that in addition to the accompanying tune.
WOT_test_3.hpl
GTO-New-42.hpt
Let me know your thoughts, and thank you for taking the time to look.