Temp related knock

[steve99]

Originally Posted by JB86'd

Nope. I was just doing some normal driving along with some spirited runs to high rpms. Maybe my log is just too long.

Agree with @solidONE that log is suspect, even the time goes forward and backwards something is wrong the data fields have got jumbled up or something.

[solidONE]

Originally Posted by JB86'd

Nope. I was just doing some normal driving along with some spirited runs to high rpms. Maybe my log is just too long.

Maybe, but when you shut all the parameters off and turn on the time you'll see a very jagged zigzaging line instead of a straight diagonal line as it should be. Do some pulls from low RPM straight to redline in 3rd gear or 4th gear if you can, 5th gear if you are crazy. You will get a better idea of what going on through the entire rev range. Or do a 3rd to 4th to 5th pull from 2.5k ish to redline like I do if you can find a road that allows you to do that.

[solidONE]

Originally Posted by steve99

Agree with @solidONE that log is suspect, even the time goes forward and backwards something is wrong the data fields have got jumbled up or something.

Yeah that, or he is traveling forwards and backward through time rapidly....

Hmmm...Where is the time travel table in romraider? lol

[solidONE]

I thought I post a small update of my testing this past weekend with the +100*f temps. I dialed it to pull over +.5 degree of advance at the upper RPM range with IAT at and over 104f. Also increase the amount of tip in retard at the upper range past 104*f IATs. Doesn't seem to be quite enough to prevent the computer from pulling even more timing particularly after up shifting to 4th and 5th gears. While there is a slight improvement, it still looks like I need to do more tweaking.

After changes:
http://datazap.me/u/solidone/stg1-20...12&zoom=40-328

Before changes were made for reference:
http://datazap.me/u/solidone/stg-1-f...12&zoom=63-368

Notice how once I shift to 5th, the knock correction really starts to kick in.

[JB86'd]

@steve99 @solidONE Okay guys so I went back to the future and realized I had saved the datalog from OFM while I had it organized by FLKC values instead of Time. SO here is it correctly organized. There are two pulls in there to redline.

This datalog is a bit concerning now that I'm looking at AFR and seeing 15-16:1 at around .5 engine load as high as 5000 rpm.
http://datazap.me/u/joshbustos86/frs...ata=1-4-6-9-12

@solidONE you have a quite a bit of FLKC in the upper RPMS there..I've never had more than -1.5 at any point. What kind of a gas are you using?

My ambient temps for my datalog were at about 95 degrees F, and all the timing I've pulled still wasn't enough to get rid of the FLKC.
I took a very spirited drive last night when it was 80 deg F out, and my IAM went back to a solid one. So now I'm convinced that it's very temp related.

Again, here are my changes compared to the original B01C map. IAT compensation combined with Base Timing pulled is really starting to add up though...

[Kodename47]

-0.35 and -0.7 degrees less aren't really a lot of timing to lose.


You only hit 0.5 load at high RPM if you're off the throttle so those AFR figures aren't anything to worry about.


Do any of you use @vgi's tool to look at this type of data? I find it quite good as you can use it to check all kinds of things and find constants, especially with the filters etc.

[JB86'd]

Originally Posted by Kodename47

-0.35 and -0.7 degrees less aren't really a lot of timing to lose.


You only hit 0.5 load at high RPM if you're off the throttle so those AFR figures aren't anything to worry about.


Do any of you use @vgi's tool to look at this type of data? I find it quite good as you can use it to check all kinds of things and find constants, especially with the filters etc.

thank you for the clarification there, now I won't feel bad pulling a bit more timing if I need to. Okay good to know, I think my AFR looks good at higher engine loads with throttle when comparing to the OL fuel tables.

I have not used VGI's tool, I searched for it online but couldn't seem to find it. Do you have a link to it?

[Kodename47]

Originally Posted by JB86'd

I have not used VGI's tool, I searched for it online but couldn't seem to find it. Do you have a link to it?

http://www.romraider.com/forum/viewt...p?f=32&t=10481


Use the log stats screen.

[solidONE]

Log some wot pulls to redline shifting from 3rd to redline then 4th to redline then 5th and see if you don't get as much knock correction by the time you hit 5th gear. If I stayed in 3rd or 4th gear without up shifting I get no more than -0.69 degree of knock correction.

[JB86'd]

Originally Posted by solidONE

Log some wot pulls to redline shifting from 3rd to redline then 4th to redline then 5th and see if you don't get as much knock correction by the time you hit 5th gear. If I stayed in 3rd or 4th gear without up shifting I get no more than -0.69 degree of knock correction.

I can only shift from 3rd redline to 4th..I don't have anywhere to do over 100mph.

[solidONE]

Originally Posted by JB86'd

I can only shift from 3rd redline to 4th..I don't have anywhere to do over 100mph.

3rd to 4th should be good enough. I use shell 91 btw

Edit: I also make sure my IAM is at 1 before I start logging to make sure I record in the logs the amount of correction the computer is making while trying to apply the maximum amount of advance programmed in the tune. Also, it makes sure I catch in the log what went on if and when the IAM does get dialed back. Since we are trying to log the effect of high temperatures on knock corrections it is pretty important, IMO, to log the intake air temperature as well.

[solidONE]

Originally Posted by solidONE

I thought I post a small update of my testing this past weekend with the +100*f temps. I dialed it to pull over +.5 degree of advance at the upper RPM range with IAT at and over 104f. Also increase the amount of tip in retard at the upper range past 104*f IATs. Doesn't seem to be quite enough to prevent the computer from pulling even more timing particularly after up shifting to 4th and 5th gears. While there is a slight improvement, it still looks like I need to do more tweaking.

After changes:
http://datazap.me/u/solidone/stg1-20...12&zoom=40-328

Before changes were made for reference:
http://datazap.me/u/solidone/stg-1-f...12&zoom=63-368

Notice how once I shift to 5th, the knock correction really starts to kick in.

After some more minor tweaks to the tip in retard and base ignition tables. IAT's didn't quite hit +104f in this log but satisfactory results.

95f temps.
http://datazap.me/u/solidone/stg1-20...12&zoom=42-333

Should I keep going until I see no more knock correction after upshifting to 4th gear?

Edit:
Base timing difference from the OTS 91:

IAT Compensation:


Edit 2:
Another log with 105f ambient temps and +104f IAT's with above changes:
http://datazap.me/u/solidone/stg1-20...12&zoom=54-354

95f ambient:
http://datazap.me/u/solidone/stg1-20...12&zoom=32-329

94f ambient:
http://datazap.me/u/solidone/stg1-20...12&zoom=31-365

Now I'm wondering how long it takes the computer to register tip-in knock and knock in general before pulling timing? Instantaneous? Half a second?

[solidONE]

Just wanted to add another variable that may contribute to knock due to temperature. The 2 logs below are both running the same tune with the target AFR set to 12.2:1 at the point marked.

At 105f ambient and 109.5f IAT measured, the afr was 12.82:1 @6500rpm
http://datazap.me/u/solidone/stg1-20...6-194&mark=161

At 69f ambient and 73.4f IAT measured, the afr was 12.06:1 @6500rpm
http://datazap.me/u/solidone/stg1-20...6652&mark=6618

This tells me that to get any sort of consistency with the afr with this much temperature difference the temp compensation for the MAF really need to be dialed in. (this i've already been well aware of from playing with the maf scale in different temps but was advised to leave the maf compensations alone) Either that, or the stock O2 is also sensitive to temperatures. Tho without an exhaust temp reading in the log it's hard to say.

[Kodename47]

The stock O2 loses consistency if it changes temperature and with changes in exhaust pressures. Over 2 different runs its hard to tell which is more accurate.

If the temperature comps are making it worse, just try flattening out the table.