Some Knock up top

[Akumazeto]

r53 tvs 900 cat cam 469. running e85. Getting some un acceptable knock up top. Threshold is 110-115 and I will see a spike of 170 or so at or above 7200. Motor will wind out to 7800-8200 but this knock is not what I want to see. Ideas?  Log attached. 

 

 

 

e85_current (1).llg

[Adamw]

It looks more like you havent balanced your levels to me.  I would also generally want the levels a bit higher than what you are using.  Also, since you are wasted spark you cant have individual cyl control, you will notice cyl 1 & 4 knock levels are the same and 2 & 3 are the same.  You should assign both cyl 1 & 4 to knock table one and cyl 2 & 3 to knock table 2.

I suspect the spike you are seeing actually happens after you lift off - the PC logging is not fast enough to see exactly when it happened.  It is pretty common to get a spike like that when you lift off at high RPM, I normally lockout knock somewhere before the normal redline and and have a TP lockout somewhere around 40% to avoid this.  

[Akumazeto]

Adam how to go about doing the lock outs like you said. What am I looking for exactly? 

[Adamw]

Example below, say my redline or normal shift point was about 7000, I would set my RPM High lockout to 6500 so that it is disabled before a limiter is hit - this is well beyond the torque peak so in most cases knock is unlikely at this RPM.  Set the TP lockout to 40%, this will disable knock when you lift off from high RPM to avoid the overrun spike like the example in your post above.  And experiment with the TPS delta lockout also, you want knock to disable during a heavy throttle stab which can cause "false knock" and trigger retard when you dont want it.