Tuning for 0 knock, having an issue with one area
Tuning for 0 knock, having an issue with one area
I've been refining my tune when time allows (and when my datalogger allows lol) and lately I've been having an issue with one area of my map. I'm trying to shoot for 0 knock in any portion of the map, but I have one spot in particular that's giving me a hard time. Right around 2190rpm's I have 2 counts of knock pop up, and by 4027rpm's it's sitting at 3 counts then goes away. According to my logs, my timing sits at 10* when it shows 2 counts, then jumps up for some reason to 17*. I can't find 17* anywhere on my timing maps for that load percentage (only at 111.2% at the time of 3 counts) and rpm, although there is a 17* in a cell 2 places over and down. I know 3 counts isn't alot considering what the stock tune was showing (upwards of 15 counts in certain areas), so should I even bother pulling my hair out to get rid of this little annoyance? Also for some reason it seems the warmer the weather gets, the less knock I see at all.
WOT in 3rd and 4th doesn't have any issues. 0 knock all the way to redline. It's only on the lower rpm part throttle where load starts to ramp up as the turbo starts spooling. Out of boost ramping up sits consistently around 12.3-12.5 and onset of boost drops to 11.9 during the first 1-3 psi and then drops even further to around 11.3 consistently. I just swapped a walbro 255 in yesterday to replace the Evo 9 pump I had been running, so if anything the afr's would be a tad richer.
yeah low load knock sux!
I was trying to tune mine out before someone tried to kill me!
I was going to flash back to stock to see if it still did it! I suspect its fine, because its only intermitant...
I was trying to tune mine out before someone tried to kill me!
I was going to flash back to stock to see if it still did it! I suspect its fine, because its only intermitant...
Glad to see I'm not the only one with this issue then lol. I'm going to take a look at the stock map in the morning and see if there are any large differences there compared to mine. Only thing I can think of is the large jump in timing causing it, although ATM I'm not sure why it keeps adding timing above what I have it set to. Perhaps something to do with the lean spool timing advance map?
Glad to see I'm not the only one with this issue then lol. I'm going to take a look at the stock map in the morning and see if there are any large differences there compared to mine. Only thing I can think of is the large jump in timing causing it, although ATM I'm not sure why it keeps adding timing above what I have it set to. Perhaps something to do with the lean spool timing advance map?
your sure your low octane timing map values are less than your high octane timing map values?
I purchased a vendor map (which was garbage and ive since tuned the car myself) where they had modified the high octane timing values but did not touch the low octane timing, this led to points where my low octane timing values were higher than my high octane values
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your sure your low octane timing map values are less than your high octane timing map values?
I purchased a vendor map (which was garbage and ive since tuned the car myself) where they had modified the high octane timing values but did not touch the low octane timing, this led to points where my low octane timing values were higher than my high octane values
I purchased a vendor map (which was garbage and ive since tuned the car myself) where they had modified the high octane timing values but did not touch the low octane timing, this led to points where my low octane timing values were higher than my high octane values
As for the low octane timing map, the same thing applies...both were the same for tuning purposes and now the values are retarded a few degrees for a "just in case" incident. I just still can't figure out why it keeps advancing timing at the onset of knock. Even after looking at the boost enhancement adv/ret map it shows advancement added on to the timing map, but no where near the load range that this issue is at.
After looking at the stock timing map it shows 20* timing advance in that same load area, and right now I'm only at 10* currently. I wonder if I don't have enough timing and the sensor is picking up the ignition on the downward stroke of the piston?
Last edited by Slo_crx1; Dec 31, 2007 at 08:43 AM.
10* or 20* BTDC is not downward stroke. It's also impossible to get pre-ignition on downward stroke. You'd probably melt the pistons if you did.
Why did you reduce it from 20 though? Low loads work with stock values just fine usually.
You should just post pics of the map. Your original post is kind of vague.
Why did you reduce it from 20 though? Low loads work with stock values just fine usually.
You should just post pics of the map. Your original post is kind of vague.
Last edited by mplspilot; Dec 31, 2007 at 08:56 AM.
10* or 20* BTDC is not downward stroke. It's also impossible to get pre-ignition on downward stroke. You'd probably melt the pistons if you did.
Why did you reduce it from 20 though? Low loads work with stock values just fine usually.
You should just post pics of the map. Your original post is kind of vague.
Why did you reduce it from 20 though? Low loads work with stock values just fine usually.
You should just post pics of the map. Your original post is kind of vague.
Here's a shot of it currently...
The only thing that might be causing the issue is the group of cells around the highlighted area in the fuel map that's set at 13.4afr, probably should go a bit richer for them, although in comparison the stock afr map for that range is much leaner with much more timing advance. Only the low octane stock map drops down to 12.6 afr in that load cell, and the low octane map for my modded rom is in the 12.8 afr range.
You have a log? You've got the timing jumping from 4 to 11 degrees in adjacent cells. That can cause knock. You actually have big jumps in timing from 2500 - 3000 all the way up to 200 load.
I reduced the timing in that section because I had originally been seeing around 15 counts of knock in that area during the warmer months.
Here's a shot of it currently...
The only thing that might be causing the issue is the group of cells around the highlighted area in the fuel map that's set at 13.4afr, probably should go a bit richer for them, although in comparison the stock afr map for that range is much leaner with much more timing advance. Only the low octane stock map drops down to 12.6 afr in that load cell, and the low octane map for my modded rom is in the 12.8 afr range.
Here's a shot of it currently...
The only thing that might be causing the issue is the group of cells around the highlighted area in the fuel map that's set at 13.4afr, probably should go a bit richer for them, although in comparison the stock afr map for that range is much leaner with much more timing advance. Only the low octane stock map drops down to 12.6 afr in that load cell, and the low octane map for my modded rom is in the 12.8 afr range.
Check this thread out and see what people are doing:
https://www.evolutionm.net/forums/sh...d.php?t=308720
^^ beside above comments about timing... You retarded timing too much for stoich AFR areas.... I would replace the load zone 0 through 120 with stock high oct timing map and start all over again.... Meaning, log and reduce timing as necessary... Also, is your car really hitting 240... 220 timing will definately produce knock from 3500 to 4500.... It is too aggressive for my test even for 93 oct...
^^ beside above comments about timing... You retarded timing too much for stoich AFR areas.... I would replace the load zone 0 through 120 with stock high oct timing map and start all over again.... Meaning, log and reduce timing as necessary... Also, is your car really hitting 240... 220 timing will definately produce knock from 3500 to 4500.... It is too aggressive for my test even for 93 oct...