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thoughts on my datalog


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2nd gear is too short and is not under enough load. You really need a 3rd gear pull from 2K-redline to properly monitor the tune.

 

For some reason the VAGCOM cable that I have just doesn't like logging 3rd gear:(

It'll log the first part of the run until about 4k just fine. But from 4k-redline it's a crapshoot.

Sometimes the data points are spaced really far apart. Other times it decides to leave 4k-~5k blank and then log the last 500rpm.

Either way, I haven't been able to reliably log 3rd gear.

(I've replicated this w/ a couple of laptops and no, I'm not bumping the cable. It seems like somewhere ~4k I lose the connection w/ the ECU and don't get it back until after the run.)

 

Every once in a blue moon, I get a decent 3rd gear log like this one. I just wish I had remembered to log some of the other parameters.

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I was reading the big data logging thread and saw this regarding Leonardo's tune

 

...

KC keeps dropping. The initial KC drop of 2 usually indicates Feedback Correction.

 

However, watch the KC just keep dropping as rpm increases. Feedback correction will increase as time passes as long as there is no additional knock event.

 

If KC keeps dropping in increments not equal to 2, that usually indicates fine learning knock correction or worse, IAM dropping. It could be knock in this log or it could be knock from a previous event. It doesn't matter. It's dropping in a rpm range that I would be uncomfortable with.

...

 

Is KC dropping in increments of 2 specific to TDC/Jon maps? Or is it a rule of thumb?

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I was reading the big data logging thread and saw this regarding Leonardo's tune

 

 

 

Is KC dropping in increments of 2 specific to TDC/Jon maps? Or is it a rule of thumb?

This should go for any maps/roms unless the default feedback correction value has been changed in which there is no reason to do so.

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This should go for any maps/roms unless the default feedback correction value has been changed in which there is no reason to do so.

 

Hmm, I guess I'm a little bit confused. Most of the stock or Cobb stg1/2 logs that I've seen have KC decreasing w/ RPM in increments of .5.

 

PS it seems the stars aligned just right tonight...usable 3rd gear logs!

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Cobb uses the stock DA table that's why your KC looks like that. Most tuners use a flattened DA table (constant values in the high load regions and stock values in low load region).

 

Just plot your total tiimng versus rpm (x-axis).

 

Knock can also be indicated by IAM dropping. Depending upon the tuner, FLKC can drop indicating knock. The stock rom does not have FLKC listening above 2.1 g/rev so in WOT logs, usually you will not see FLKC dropping. However, it may be active due to previous knock. It's confusing unless you understand the logic.

 

OP, your logs look fine.

 

Chubien, plot this timing versus yours. You'll see what's going on. At 3700 rpm, you should be running 15-15.5 degrees total timing like this map, but your rom suddenly adds an extra 2 degrees which your tuner probably didn't know the ecu was going to do so it resulted in a knock.

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Chubien, plot this timing versus yours. You'll see what's going on. At 3700 rpm, you should be running 15-15.5 degrees total timing like this map, but your rom suddenly adds an extra 2 degrees which your tuner probably didn't know the ecu was going to do so it resulted in a knock.

 

Ok, thanks for the input.

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