I am getting between 8-17* of KR when I am rolling on the throttle (partial) between 3-4K rpms. It happens erratically. Sometimes it doesn't do it as bad and other times I can feel the car fall on its face for those 1000 rpms and then it takes off smoothly again. I have Pacesetter longtubes, stock maf, throttle body and intake. I was just curious if anyone else with a similar size cam and setup had this problem? My Ltrims are negative and lock at 0 at WOT. I have slight knock in some other places but I can fix that. I have pulled timing in that rpm/ g/cyl area and it doesn't help. Any suggestions would be greatly appreciated. Should I raise the VE table in that MAP/rpm range? If I increase the VE will it make my ltrims more negative?
Thanks for the help
Matt

 

Log the gms/cyl that you are at when the KR is occurring and pull out the corresponding amount of spark based on the gms/cyl vs. RPM. If you still see the same or near the same amount of KR, then it is false or something is seriously wrong. Another option is to run the tank all the way down and put in 4+ gallons of 100+ octane and see if the KR changes at all. If the octane changes the amount of knock retard, then you are seeing true knock with the lower octane fuel and chances are either:
a.) there is a mechanical problem in the motor
b.) the cam was misground or installed advanced with the wrong intake/exhaust centerline and is creating too much cylinder pressure.

If you'd like, you can email me your edit file at heyseth38@aol.com and I'll write it with a tried an true file for the G5X2 and it may very well take care of the issue.