6.0 LS Turbo - Intermittent Knock

Hey y'all,

I'm having some issues with intermittent Knock Retard kicking in while tuning my car. The setup I am tuning is a gen 3 6.0 LS with 76mm turbo on a stock GM ECU. At times, I can make a pass down the track with no Knock Retard issues whatsoever. Other times, with no changes to the tune, Knock retard will kick in as soon as my burn out and continue throughout the length of the pass. My fueling and IAT and commanded spark all seem where they should be so I'm stumped. I have attached two log files running the same tune; one with Knock Retard, and one without. I have also attached the tune file they are running. If anyone has any insight to this issues I'm all ears.

Thanks for the help!

Could it be just on the cusp of triggering the knock retard - usually just short of it, but sometimes there's just enough heat in the engine, air temp's high enough, boost just high enough, etc. for the engine to have enough 'knock' to trigger the retard?

Have you tried pulling the base timing back a degree or two to see if it still gets triggered?

Yeah I thought the same thing, however, I’ve already tried that and still had the same problem. Also looking at the tunes didn’t seem to corroborate a heat issue. I’m wondering if the factory settings for the knock sensors is just too sensitive above 50KPA. I think I’m gonna change that table to 2.0 and 50KPA and up.