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Datalog Assist

2791 Views 6 Replies 2 Participants Last post by  turbolarry
Kinda new to the whole tuning thing and recently installed an XEDE. Here is a 3rd gear datalog pull using CommsLog. I've got some graphs in it as well. Just wonderin if anybody out there can tell me how it looks as far as AFRs and knock and what areas I need to work on. I am under the impression that AFRs of 11:1 is a rule-of-thumb target. Is that across the board? If so, my AFRs start out lean down low and get real rich up top (almost 9s). ANyway, any input?
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Can you post the data in a spread sheet or another way? I can't veiw it.
Actually it is in Excel, but it's zipped up...I have it loaded up to my webhost. If you click on the link and download it, then unzip it, you should be able to open it in Excel...thanks...let me know if there are any problems or PM me so I can give you my email directly and send it that way....
okay...maybe this will help some..figured out how to make em JPGs to upload.

SOMEBODY please tell me how these graphs look. Am I right in assuming the my AFRS are lean down low (13s) and rich up top (9s)? Is the target 11ish? I'm pretty sure I'm runnin hella rich cuz I am guzzlin gas like crazy, even more than I think I should. I used the formulas:

Timing=(Timing Shift Out*100)/255
Boost=(WG Sol Out*100)/255

Am I correct here?

How bout the knock/timing graph? How bad/good does this look? Hows the boost graph lookin? I'm still learnin about this tunin stuff and wanted to get an assist on problem areas as well as some hints on what type of changes and where in XMap...


Yeah, I've posted in EvoM on the Vishnu forum, nobody seems to be helpin me out there either, so I figured I'd try here.


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From the looks of the graphs it's running lean before 6800 RPM's. This is what I see;
The AFR's are too lean between 3000-6500 RPM's (hovering around 11.5?). This is also indicated by the knock graph (spikes) and reduced timing. Just after 6500 RPM's the AFR's go rich, knock spikes go away, and timing starts going up.
Your injectors are also maxed out... way out, 95% @ 6000 RPM's. Ideally, injector should not run beyond 80% duty cycle From the graph it looks like they cross 80% at 5000 RPM's.
Is this on CA's fine 91 octane?
How much boost are you running?
What turbo are you running/boost doesn't come on till 4000 RPM's? Please complete your car's profile when you can.
I've never used XEDE so I can't really say where to start. This is just what I see in the graphs.
If your really new to all this, and you can't find someone close to you to help, you might want to consider professional help.
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Actually that Duty Cycle is the Factory Boost Solenoid, not the injectors. But yeah, I'm on 91 Cali Gas. My mods are actually pretty minimal, Works Drop In Filter, Hard MAF pipe and a Walbro Pump, that's it. The boost I have goes up 22-23 then tapers to about 21. From Some of teh other EvoM member's I'm understanding that around 11:1 is where to shoot for. Yeah, I'm kinda new and Vishnu is only 80 miles from me. I am goin to check them out here shortly, just wanted to get some basic knowleddge of the system so I can do a little tweakin myself. I really appreciate your help.
aresix6 said:
From Some of teh other EvoM member's I'm understanding that around 11:1 is where to shoot for.
Every car is different. Don't trust anyone saying "these numbers are good for this," or "this number should be safe." You have a capable logging capabilities and your ideal AFR will be different; considering on our sh!tty 91 octane, knock, ignition timing, boost, air temp., etc. Start learning what adjustments here lead to results there, and what are the danger/warning signs to look for signs to look for in your logs.
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