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Jul 8, 2011 | 03:20 PM

#941

fordomatic69

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Joined: May 2009

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From: Caledon, Ontario, CANADA

I would still like to see the PV be able to export the log file to a .dif file for viewing in LogWorks 3 (The DashDaq can do this so I think it's possible to get the PV to do it).

Jul 8, 2011 | 05:22 PM

#942

Sam2010

Outstanding HDF Member

Joined: Aug 2009

Posts: 2,858

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From: Puyallup Wa.

Quote:

Originally Posted by JustDennis

It will show in the log as Spark Knock F and Spock Knock R. I believe in the selection it says Front Spark Knock Retard and Rear etc. You are looking for where the bike retards the timing you have so PV tune can adjust the timing back in your calibration. Pick the Retard channels for logging

Spark Knock F = Front Spark Knock Retard
Spark Knock R = Rear Spark Knock Retard

Thank you very much all your efforts here helping us its very much appreciated. I was confused with the spark knock selection could add "retard" on selection instruction? I did not recall reading it but that does not mean it was not there. It makes sense now that you point out the log tuner is looking for Retard. I think I am good to go for the time being.

Jul 8, 2011 | 05:24 PM

#943

Sam2010

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Joined: Aug 2009

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From: Puyallup Wa.

Quote:

Originally Posted by fordomatic69

Knock retard or (KR) is the number of degrees the ECM is retarding your ignition timing in order to eliminate knock. There is a knock sensor mounted to each cylinder and when the sensor detects knock, it instructs the ECM to retard ignition timing to prevent knock.

If you are logging and you see no KR, then you can advance timing a little, then log again (especially log at Wide Open throttle or WOT). Keep advancing timing until you see some KR happening, then either back off the timing or add a few points of fuel to see if you can eliminate the KR.

The most power you will get is when you are running just on the edge of KR without actually seeing any in the logs. Quality of Fuel will play the biggest part in logging for KR because if your timing is advanced and you put in lower quality fuel, your knock sensors could go ballistic and you actually end up losing HP and performance bcause the ECM is compensating for the Knock by retarding your timing.

Thank you for the additional input.

Jul 8, 2011 | 10:59 PM

#944

iclick

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Joined: Sep 2005

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From: Baton Rouge, LA

Quote:

Originally Posted by fordomatic69

There is a knock sensor mounted to each cylinder and when the sensor detects knock, it instructs the ECM to retard ignition timing to prevent knock.

Actually, most (all?) knock detection today has no external hardware mounted to the engine block to detect knock. Ion-sensing knock detection, the method used in Harleys at least as far back as '07, does not use a sensor that is externally mounted on the engine. The name "ion sensing" is derived from the fact that as detonation occurs ionization at the plug tip changes the resistance to fire the plug. The actual detection of this change in resistance is internal to the coil and the signal is sent back to the ECM.

Jul 9, 2011 | 06:24 AM

#945

papifun

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Joined: May 2008

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From: Quebec,Canada

i monitored the spark knock while riding.. it has always displayed zero. is this normal ?

Jul 9, 2011 | 07:53 AM

#946

fordomatic69

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Joined: May 2009

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From: Caledon, Ontario, CANADA

Quote:

Originally Posted by iclick

I stand corrected. My Dodge Magnum hemi has knock sensors physically mounted to the engine. The downside is that sometimes they can produce "false knock" when the displacement changes from 8 cylinders to 4 and back again. I log sometimes 5 degrees of KR during the transition of 8 to 4 and back again.

Jul 9, 2011 | 07:54 AM

#947

fordomatic69

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Joined: May 2009

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From: Caledon, Ontario, CANADA

Quote:

Originally Posted by papifun

i monitored the spark knock while riding.. it has always displayed zero. is this normal ?

If you are using a canned tune with good quality fuel, yes 0 knock is normal and very desireable.

Jul 9, 2011 | 08:27 AM

#948

Heatwave

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Quote:

Originally Posted by iclick

Iclick, can you explain something to me on how the PV knock adjustment works? I used the PV Basic tuner to tune for knock. I'm unable to use it for tuning VE since I'm using the stock NB sensors and my dyno-tuned map AFRs are too far off from 1.00 lambda. So I figured I would use the spark adjustment capability of the PV basic tuner just to see what I would get.

I logged a number of good runs that varied alot. The dyno-tuned map was pretty good from a spark perspective but there were a few areas where there were small knock events. Mostly out near 70-90 kpa and 3500-4000 rpms. Again these were relatively small events but I thought I would let the Tuner make the appropriate adjustment.

The tuner lowered the spark and when I logged again the knock event was either gone or reduced to nearly nothing. What I did notice was that the performance of the bike from just this small timing adjustment made a noticeable reduction in performance that could be felt from the saddle.

Is it possible that the basic tuner algorithym is too aggressive in lowering the timing when it reads a knock event. In any case I went back to the original dyno-tuned map and immediately felt the improved performance. Is it possible that PV tuner is lowering the spark advance more than the ECU knock retard is lowering it which is why I feel the reduced power?