+1 Knock retard okay?

merkyworks

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Wanted to see what the general consensus is on some knock retard I'm seeing and if I should be concerned before I install my Gen2R this weekend.

Car has 25K miles and stock power wise, have catch cans on both sides with passenger having oil to drain like normal and driver is always clean. Since I live in hot Texas weather I have also upgraded to VMP triple pass HE. Had car dyno'd (dynojet) recently before I stalled the VMP HE and it put down 487 RWH / 473 RWT.
12GT500Stock_DYNO.jpg

Measureing KR with Aeroforce gauge when doing a 3rd or 4th gear pull I typically see -1to-2KR at start, moves to 0KR but then around 5-5.5k rpm is see +1.01KR till redline. I have tried different gas station and still see the same results. With car being stock and showing good power numbers should I be concerned about the +1KR or is that considered okay?
 

sleek98

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Your tuner will have to change the timing curve for the tvs so it doesnt really matter what you are seeing now. You will want to make sure that the new tune is setup correctly.
 

jn2

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On the copperhead ECMs(11+) positive knock retard means the ECM is pulling timing. The stock tune has the maximum set to 1* of retard, so if you are seeing +1* right now but the car is running fine and there is no audible knock, then chances are it could just be blower, engine, or exhaust noise. If your tuner was to increase the retard value the ECM may end up pulling even more timing bc of the sensors/noise they pick up.

When ever your tuner sets up your new tune for the TVS they will adjust your Borderline Knock table by lowering the amount of timing you will run as load increases.

I am in the process of tuning a 2010 with a TVS on it and the knock sensors pick up a ton of noise so we had to go through quite the troubleshooting process to determine whether the knock was real or false. I am sure your tuner will do the same if they do run into any KR issues.

What we did was:

- 1 step colder plugs gapped @.028"
- Added VP Octanium
- Lowered spark advance to 12*
- Ran the engine richer(.75 lambda)

The results of all these things led me to the conclusion that the sensors were picking up random noise and it thought was knock when it was not
 

merkyworks

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okay got it, will make sure to talk with my tuner about this. Thanks for all the great info!
 

rotor_powerd

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Head coolant temp and IAT2 will both knock timing back pretty aggressively even on a stock car. Your tuner should adjust the values in both tables to increase the thresholds before timing starts getting pulled.
 

merkyworks

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Interesting thing happened today while driving to work.

Was on a not so smooth road and got on it a little in 3rd with RPM's in the 2-3k range and I saw KR go to +1 which I thought was strange. Then I realized I had traction control on and being a bumpy road I figured traction control must have kicked in. Now I'm wondering if traction control is maybe a variable for KR in certain instances.
 

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