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Hello I have a K24A2 with a gt35R turbo and I am getting knock in the 10psi range from 4k-6k rpm. After 6k no knock is record and the timing is 15 degrees.
the knock count on kpro shows 53, which i know is very high.
My ignition timing is a 10 degrees which I know is on the low end.
My next step is to set the ignition timing lower to 8, then 6 degrees.
My question is what is considered too low of an ignition value? Also if I continue to set the timing lower and knock still occurs what would by the next step I should take??
I want to add that my AFR is at a steady 11.5 during all of this.
First thing is to make absolutely sure the true TDC and the ECU calibration for TDC are showing the same figures. Either may be wrong - note, that's the piston TDC as sometimes crank pulley/flywheel TDC pointers are a little out and have to be corrected first.
Something overlooked, sometimes, is the affect camshaft selection, timing and mechanical compression can have on the engine combustion characteristics. There is also the question of the fuel used?
91 octane was used here.
DO you know how to verify TDC on the Kpro software?
I would assume you could load zero advance through the rpm/load range? What does your documentation say?
What is happening to the CAM angle in the area with knock? Perhaps it's not advanced enough. or... too much.
What is the VTEC switch point?
If lowering the igntion timing doesn't eliminate the knock, then the cause isn't the ignition timing.
Have you tried colder plugs? Perhaps you are having pre-ignition due to a plug that is holding the heat.
cam angle is set to 20 degrees and its showing 20 degrees in the datalog.
vtec is set at 4400rpm.
I have the correct plugs for this type of setup. Many have used the plugs I have for the power level its making.
With a turbocharger engine the cam advance needs to be less than stock. This is because a turbocharger generates much more exhaust back pressure than a naturally aspirated or supercharged configuration. The higher the back pressure the more cam retard is needed. With small turbos and stock catalytic converters you may need to retard the cam fully to 0 degrees at 8000 rpm
i just read this on the kpro website, is this implying that cam angle should only be set to 0 while in boost?? but it also states this should happen with a smaller turbo setup, what if I have a big turbo? is this still the case?
I'd suggest confirming with audio knock detection that the engine is in fact suffering from knock.