Ok, have fun...:cheers:
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Ok, have fun...:cheers:
Hey Joe, I'm too tired to spend much time on this, but I got a great BBL log file from Road Atlanta with all the PID's you recommended. Here's a snapshot of me heading down the straight for the nasty turn 10a. Let me know what you think from these readings. See anything I should be worried about?
Some observations:
- measured AFR is richer than commanded AFR,
- LTFT's are almost pegging on the high side,
- IAT shows 90°F... was outside air really that hot...?
What are all your mods...?
You may need to do:
- recalculate B4001 IFR,
- correct VE table (see AutoVE tutorial),
- correct MAF (using AutoMAF),
- set B3605 AFR, B3618 PE AFR and B3616 PE Enable.
How many miles do you have on your Z06...?
If you have many miles, then the O2 sensors may need replacement and the MAF may need cleaning (use MAF cleaner not Brake cleaner).
Post your log file and tune file.
Are you logging no more than 24 channels...?
Cool stuff Joe, I'm on my way out. Quick response is when you are running 20 minutes at 5-6k rpm in atlanta, yes it is that hot. This is why I kept bugging you guys for how to log oil temps too. I ran 270-280 oil temp most of the time. Was in 290's two weeks ago, but went with 15w50 Mobile1 Synthetic this time and took the straight in 5'th gear. That will keep me in 270's thru tomorrow. I'll be getting an oil cooler after this event. I have never ever been able to see the IAT, so I don't even know that 90f is high. Nor do I know what will happen to IAT when I put a oil cooler on?
Mods
Fast92 - LS2 TB, Vararam intake
LG Pro Street headers, xpipe no cats
Of note to me is all the talk about the Vararam causing heatsoak. Perhaps the 90f IAT is related to the Vararam in some way, I don't know, but something to dig into.
My monster log file attatched. Please remember its not street driving and its not a dyno run. Its real road racing in 90 degree heat at one of the nastiest tracks in the world. And all I care about is tuning my car to better stand up under these circumstances. That said, your input is greatly appreciated.
Yes, I am alluding to heat soak of the IAT and/or intake plumbing...
Hi Joe, lets start with this as I know what the MAF is and will check both it and my new TB for dirt/oil/anything ugly.
From some quick searches, having 90degree IAT on a 88degree day, with oil temps in the 270-280 degree range, can't be considered heat soak. Air temp pretty much same as the outside air while the engine compartment is cooking seems to me to say that the Vararam CAI is working very well.
Please explain why this looks like something alarming to you.
Oh, I didn't realize your outside air temp was 88F... I was assuming something like 70F... so that is definitely not heat soak.
Good log, very interesting... 43+ minutes... :cheers:
Log shows:
- LTFT's ranging from +12% to +25% (pegging)... indicates MAF may be reading low,
- WOT: actual AFR is richer than commanded AFR by at least 1 AFR,
- WOT: actual AFR is going as low as 11.0,
- CL: actual AFR at stoichiometric equal to commanded AFR... indicates wideband is functioning,
- closed throttle: actual AFR spiking lean (is DFCO enabled...?),
- fairly consistent knock at WOT,
- injector duty cycle hitting 100%;
- there are a few places at WOT 6000+ RPM where MAF is well under 300 g/s;
I'm not sure, but I think maybe the MAF is dirty (only clean with MAF cleaner)... check the air cleaner filter also;
Maybe do this (in this order):
- recalculate B4001 IFR (even if to just sanity check it),
- redo the VE table (AutoVE, in OLSD) if you haven't already (get a log in OLSD anyway),
- correct MAF (using AutoMAF, in OLMAF with B0120 zeroed), get MAF ben to 1.00, get some logs;
Set high load areas in B3605 OL AFR and B3618 PE AFR to something like 12.6.
Once you get the actual AFR matching the commanded AFR, then your injector duty cycle will probably go down a bit.
Questions/Comments:
- you're NA so AFR 11.0 is a bit too rich;
- have you considered running a few laps in OLSD...?
- I don't believe the oil cooler will affect your IAT.
- why is knock being indicated...?
- check if motor ingesting oil thru PCV...?
- does engine top have carbon deposits (have you ever had top engine cleaner)...?
- how many miles on engine...?
- sawtooth pattern on KR indicates it may be real knock (especially during WOT pull);
- from frame 10006 ECT starts to show higher trend... why...?
Create some maps like the one attached to see if you can correlate KR to something.
My $0.02... :)
Thank you so much for spending the time on my log file Joe, I really appreciate it. Keep in mind I really don't know how to use your software just yet. So its going to take a while for me to even understand everything you are talking about. I'll try to answer your questions below. I cracked a rotor on the last lap of the day, so I wont be driving it till the weekend anyway. I'll get the MAF and TB checked out and new rotors by end of weekend. I'll muddle through the AutoVE and as much as I can by end of weekend. Its a good thing my desktop works because I cant even uninstall, delete registry key, reinstall and get the scan tool to read logs anymore on my notebook. I'm not going to obsess over that now that I have real stuff to learn about though. I'm sure that was a uncommon log, just imagine how that rotor cracked. You saw the speed and rpms in the straights, after that was full out brake, then back to full out throttle. Its a blast. Total Nirvana:rockon:
Thanks again, Ken . . .
Your injector duty cycle will go down as you get your tables tuned.
I'm not comfortable with knock... it's damaging effects are cumulative.
there are various conditions which promote knock:
- elevated combustion chamber temp.,
- reduction in effective octane (oil ingestion would do that),
- timing that is too advanced,
- heat sources in the combustion chamber (like carbon),
- compression ratio too high (carbon layer may do that).
granted, some engines seem to always show some knock, but engine should never be allowed to go lean under load, and timing may have to be removed as air charge temp. goes up.
Maybe it's just as well your actual AFR is in the 11's.
The scantool manual has some good info, see the section regarding maps.