TT_Vert

iTrader: (12)

the higher # KR cells are cells that I might have only populated once or twice hence the high #s. These are the average knock retard #s. Should i worry about the KR in the lower RPM at higher g/cyl as i'm rarely ever going to see this type of environment or should I reduce timing in these areas? (Note the extremely high KR cells may be a fluke as a few of them I only have one value to put into the cell hence skewing the average) The first table is with the stock timing, the last 2 are 2 deg. added to the entire table. It doesnt seem to be very consistant as to what cells are getting KR, i dont have KR in the same cells on each log, does that tell you guys anything?
Stock timing:

+2deg

+2deg


Thanks

Dave

ataylors

iTrader: (2)

what mods do you have?

TT_Vert

iTrader: (12)

4.10s, vararam, long tube headers

dave

ataylors

iTrader: (2)

how long did you drive on the current tune before you pulled these #'s?

TT_Vert

iTrader: (12)

at least 100 miles on both tunes (stock timing at +2) what could be affected by drive time? Can the Ltrims change affecting things or something?

Dave

Cheatin' Chad

iTrader: (3)

Are you driving the same loop while testing? Different conditions and terrain can affect this.

Example: If you lugged up a hill on the last log you will see more knock and in different places.

Try to eliminate as many variables as you can while testing.

TT_Vert

iTrader: (12)

im all over the road to be honest with you. Im just trying to find some type of trend where i always get KR regardless of terrain. I know based on environment the effect might be more or less KR id just like to see where the problem areas are.
dave

P Mack

iTrader: (6)

WOT could be affected by drive time because if your ltrims would be positive but they're still reset to zero then the pcm won't know to add fuel at wot.

TT_Vert

iTrader: (12)

the only thing i changed on those tunes was the timing. I didnt mess w/ PE or IFR
Would the ecm still need to learn something?
Dave

ataylors

iTrader: (2)

Drop 1* in the problem areas.. that is IF your fueling looks good. If it is lean that can cause your knock too.

TT_Vert

iTrader: (12)

dropping 1 deg will resolve the areas w/ 5 deg or KR??
i dont think i understand how KR works and how it determines what to take out

ataylors

iTrader: (2)

the PCM uses the attack rate to determine how aggressive to compensate for Knock it always takes out more than is needed to save itself then the decay rate is how slow it adds timing back in. Thing of it as when your driving and you see something in the road, you swerve more than you need to to avoid it, then you recorrect back to how you were going before. How much you swerve would be the attack rate, how long you go before you go back to how you were is the decay rate.

TT_Vert

iTrader: (12)

Sweet thanks. Does it factor in how "loud" the knock is when it retards timing? Do you have any idea what equation is used to get to the set KR? IE in some cells i see KR of 4 and other 5 etc, wondering if its just because the knock is more audible or just because its in a higher g/cyl cell?

Now that i know its not taking out a bunch more timing because it has to per say but rather as a precaution, is it safe to say i should take out 1 deg out of all the trouble areas and relog? Im assuming that would knock that KR at least in 1/2 if not even more. Or can i do 1/2 deg increments? Yesterday I actually added 4 deg total to my stock timing table and have been logging and getting very little retard anywhere (primarily in higher G/cyl areas in upper rpms which is to be expected). Not sure if i need all this timing but id like to improve my under the curve power as well as i drive on the streets alot and like to have pep

Thanks
dave

ataylors

iTrader: (2)

the Attack rate is used to calculate how much to pull, and the recovery rate is how slow it puts the timing back after there is 0 Knock

TT_Vert

iTrader: (12)

ok can you explain burst knock?


Dave