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First Logs: How are they?


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Also, in addition to AFR (you need a wideband O2 sensor for WOT...stock sensor won't read that correctly), log FBKC (feed back knock correction) and knock sum to see if there are issues with that--very important if checking a tune (see LtBlue's sticky on checking knock/predet). I like logging throttle position and MAF in g/s (I know you have voltage but...).
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Log the following parameters:

Engine Speed (rpm)

Engine Load (Direct)* (g/rev)

Ignition Timing (degrees)

Knock Correction (degrees)

Manifold Rel. Pressure (Corrected) (psi)

Mass Air Flow (g/s)

Primary Wastegate Duty Cycle (%)

Throttle Opening Angle (%)


you need to log 3rd gear from 2k to red line, WOT....you will need plenty of room. 2 of these again from 2k to redline...will be enough....MickeyD or Infamous are always very helpful in letting you know how they look.



Rehab is for quitters.
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I use RomRaider so not sure on Cobb logging systems.


In RR, there's:


Feedback Knock Correction

Fine Learning Knock Correction


You always want to check your FBKC to see if it's running negative on you, indicating the ECU thinks it has seen "knock" (pre det) and pulled timing at that moment.


You want to check your IAM to and make sure it's 1.0 (not less). If less, then either you just reset the ECU and haven't done a couple of WOT runs to get IAM up to 1 (it takes a few pulls), or the ECU says there's a knock problem and it has retarded IAM.


Make sure and read the following:

http://www.romraider.com/forum/topic1840.html (Merchgod's detailed explanation)

http://legacygt.com/forums/showthread.php?t=97539 (LtBlue)


A few bits are below.




Total = Base + (FBKC + DA*IAM + FLKC) + Other

Note: For the 32-bit ECU, the IAM will range from 0 to 1. For Cobb tables use the term “Dynamic Advance” (DA) for the Timing Advance Maximum, and “Dynamic Advance Mulitiplier” (DAM) (ranging from 0 to 1.0)for IAM.

From the formula above, you can see that Knock Correction Advance (KC) consists of three elements. How these values are determined and how they interact with one another will be discussed below.

Although exactly how the ECU determines knock (based on input from the knock sensor) is not fully understood, the result is quite simple. The knock signal is either set or clear. That it, as far as the ECU is concerned, there either is knock or there isn't. There's no level of severity that is stored or used for knock control.

Though over simplified, we could look at the knock control as a bit of a hierarchy:

• “Initial”…FBKC: ECU first checks for knock events and retards timing if necessary.

• “Rough”…Timing Advance & IAM: ECU then “adds” portions of the timing advance max.

• “Fine Tweaks”…FLKC: Once IAM is stable, the ECU then “tweaks” timing with the FLKC (either advancing it or retarding it).

(From what I understand only one of these three correction systems is active at any given time.)

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I DL'd RR V0.5.2. I don't see Feedback Knock Correction or Fine Learning Knock Correction. I do have Knock Correction Advance, Am I just blind?:iam:



Those are extended parameters, so you won't see them until you turn on the ignition. Romraider needs to identify the ecu before it will show extended parameters because not all cars have them.


Knock correction advance was a standard SSM parameter.

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