What is considered normal knock on LS1?
Thread Starter
Teching In
Joined: Nov 2001
Posts: 13
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From: Wollongong, Australia
What is considered normal knock on LS1? I have a 2001 LS1 powered Holden SS with quite a few bolt on mods that I have been tuning with LS1Edit. Car goes well but I have been finding lately that I typically experience ~ 2-3 degrees of knock retard in the 1700 - 2200 rpm range when accelerating in top gear at moderate throttle (typically 0.46 - 0.55 gms/cyl airflow). I have been progressively reducing the high octane table advance to reduce knock but am finding it is now back to factory settings & still knocking occassionally despite using high octane fuel & even octane boosters.
Can continue to reduce the advance angle further but as I didn't want to compromise power when the car is in other gears I am wondering how far to go. What do you guys consider to be normal knock for the LS1 engine?
Thanks
Can continue to reduce the advance angle further but as I didn't want to compromise power when the car is in other gears I am wondering how far to go. What do you guys consider to be normal knock for the LS1 engine?
Thanks
Teching In
Joined: Aug 2002
Posts: 23
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From: Elon, NC
Re: What is considered normal knock on LS1? He wouldn't be in PE mode with moderate driving. I'm assuming that he's talking about highway driving. I'm trying to figure out the same issue with my car. I'm selectively pulling timing to see if that will help.
Thread Starter
Teching In
Joined: Nov 2001
Posts: 13
Likes: 0
From: Wollongong, Australia
Re: What is considered normal knock on LS1? Badazzvette,
Your right, the engine is knocking whilst in closed loop mode & before PE comes into play. My selective reduction in timing over the last few weeks has reduced the magnitude of knock but not eliminated it. I wonder whether it has anything to do with the rate of change in advance angle as the PCM goes from one RPM/Airflow cell to another as I noticed that rapid changes during auto gear changes seem to induce knock?
Your right, the engine is knocking whilst in closed loop mode & before PE comes into play. My selective reduction in timing over the last few weeks has reduced the magnitude of knock but not eliminated it. I wonder whether it has anything to do with the rate of change in advance angle as the PCM goes from one RPM/Airflow cell to another as I noticed that rapid changes during auto gear changes seem to induce knock?
TECH Resident
Joined: Nov 2002
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Re: What is considered normal knock on LS1? Did you try deleted Torque Management?
I had areas of "random" knock sprinkled in my logs, but after deleted TM there is hardly any...
Maybe during those "rapid changes" TM kicks in a bit? Just a thought..
Tommy
I had areas of "random" knock sprinkled in my logs, but after deleted TM there is hardly any...
Maybe during those "rapid changes" TM kicks in a bit? Just a thought..
Tommy
