chopcop

I am encountering what seems to be random knock retard across all cylinders. I have replaced knock sensors and their harness, maf sensor, cam position, checked if the exhaust is hitting anywhere, etc. i am at a loss as to where its coming from. its an l77 motor with btr stage 2 v2 ls3 cam, chevy performance lifters, btr pushrods, and 660 valve springs. When i put the cam in i resurfaced the heads and everything was put together perfectly. i am in the process of getting it tuned by gpi but out of no where it started to get knock retard upwards of 13 degrees. I have never heard any audible knock and when i added octane booster to my fuel (im running 93 octane) it did not get rid of the knock retard. I attached my current tune file from gpi as well as my most recent log. Any ideas as to what could be causing my issue?

Che70velle

iTrader: (6)

If it’s truly knocking that hard, your spark plugs will look “peppered”. They will have specs on them that will look like someone shot a sandblaster at them from 20 feet and only a few specs of sand hit the plugs. It’s probably false knock. I’ve seen failing transmissions do that a lot to an LS as well as an exhaust rattling against something under there, broke engine mounts, etc.