Originally Posted by
1meanZ
New to OBD2 tuning, tuned OBD1 TPI for 13 years, first post here. Trying to learn and dial in my stock L31 before 383 swap.
Bone stock L31 in a '98 Tahoe with a NV4500 manual trans swap, stock "black box" ecm.
Engine lays down after an upshift just after I've applied throttle again. Looking at the logs it appears timing is getting pulled way back but there is no knock detected. I've done a few things to try and mitigate it but I'm not even moving it a little bit. Attached log and tune, looking for some thoughts on why the timing is way lower than what the base map shows when there is no knock detected and I have torque management shut off (at least I think I do).
Thanks a ton for the help. This is a unique combo with a manual trans that isn't often talked about here.