What exactly causes this? I seem to have knock around 4000-4500 rpm and even with a large amount of timing taken out it still has a kr of anywhere between 1 and 2.9 in the few pulls I have made. My header gasket is leaking pretty bad too right ne the knock sensor. Could that contribute to it?

It could be a bunch of things, the knock sensor is esentially a microphone and it works in the frequencies that knock occures. One thing that could cause the false knock that a few poeple are working with on the lnf and lsj motors is the clocking of the knock sensors, aparently they need to be facing the correct way. The heat from the leaking header could cause it as well. Or a multitude of other things that I can't quite remember at the moment.

Does your KR go down if you pull timing in the tune? Or does the KR stay the same no matter what you set the timing to at those points?


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At this particular point it knocks no matter how much I have pulled timing in those cells of the chart I went from the stock 21 to 15 with no change. usually it is 2.9 at that particular point but every now and then it shows up at like 1 instead. Also this is only during full throttle....it doesnt knock any other time.

What octane fuel? Also, what are your AFR's looking like when this is going on? Are your timing tables smoothed out?





P&P Tuning
420.5whp / 359.8wtq

Depending on boost level, throttle position, load, (and fuel type and AFR as mentioned above by Ryan), you could still have 5~10 degrees to much timing in my opinion. Look at the impact of going from High octane to Low octane tables (4~5 degrees stock) and see how much timing is pulled out....if you're at 15 degrees you could still have too much.

92 octane fuel, I had a wideband hooked up but hadn't hooked it up to hptuners yet, I do need to smooth out my spark tables. I am not running boost, just higher compression and some different cams. Turns out after hooking the wideband up to hptuners and looking at the datalog i was hitting like 16.5 afr at that point which I did not see on the gauge alone. I have since done some data logging with the high and low rpm VE table histograms to try and get a 13.7 afr. I feel like such a newb lol. you can read all day but it doesnt mean a damned thing until you actually try n do it.