Gotcha. I have a lot to learn! lol
Gotcha. I have a lot to learn! lol
Me tooOriginally Posted by snrusnak
2011 Camaro 2SS Convertible L99 Bone Stock for now
2003 Dodge 2500 5.9 Cummins QC 4x4. Airaid, 2nd Gen Intake, Grid Heater Delete, D-Tech 62/65/12, Magnaflow. Bully Dog: Propane Injection, Triple Dog W/Outlook Crazy Larry. Edge EZ, BD Flow-Max, 48RE: Sonnax Sure Cure/Transgo combination, Derale turbulator, billet input, Triple Disc, Super servo, 4 ring Accumulator. :beer
So I've done about 13 or 14 iterations of MAF tuning, always multiplying by % half, and mostly just normal driving, nothing crazy. I did a couple decent pulls, but basically working on the low MAF table and have dipped into the high MAF table a little. I feel like I'm chasing my tail. Several iterations of tuning and it seems like it's going good, getting all the cells close to 0% error. Then the next weekend I start the car up, drive around, do a few iterations and it's like 5+ % error in some areas. Swings from rich to lean too, I don't get it...
Assuming you are still tuning MAF only....
From what I understand the MAF has calculations that still reference the VE table...
I understand your frustration with the changes, but if you have it within 5% +/- thats pretty good, yes it can get better, but it might be time to move on to VE Tuning...
I had the same experience... The last MAF tune I adjusted when I was that close, I only adjust the Plus (lean) cells. Got most everything negative, then moved on..
I would go ahead and move up the MAF scale (higher in the HZ range) like you have and get everything within 5%, Then go to MAF fail (SD) Tuning....
Then come back to MAF...
Hopefully it will be real damn close...
My MAF swings got way less after I did that...
Do you have any filters in your graphs?
I can send you some that filter out anything under operating temperature, too fast of throttle increase, off throttle coasting, ETC...
2011 Camaro 2SS Convertible L99 Bone Stock for now
2003 Dodge 2500 5.9 Cummins QC 4x4. Airaid, 2nd Gen Intake, Grid Heater Delete, D-Tech 62/65/12, Magnaflow. Bully Dog: Propane Injection, Triple Dog W/Outlook Crazy Larry. Edge EZ, BD Flow-Max, 48RE: Sonnax Sure Cure/Transgo combination, Derale turbulator, billet input, Triple Disc, Super servo, 4 ring Accumulator. :beer
No I don't have any filters. The only "filter" I'm using is 5 hits per cell. That would be great thank you.
I'm MAF only. I didn't realize until I started reading, watching videos, and actually went into my ecm to tune that SD was disabled. So it was tuned MAF only by the person before me. I need to read up and learn how to tune the VVE tables so I can start working on that I guess. I've read that big cams cause issues (reversion pulses or something) with MAF only at low rpm (low airflow velocity). I have a btr4 so that may be an issue lol.
Thanks for the help.
So I have a question since I seem to be chasing my tail from lean to rich. Instead of logging driving through a bunch of gears at different conditions, would it be better to just do some logs of pulls holding a single gear? That way it would be steady, no weird fluctuations during shifting, etc. Like put it in 3rd gear and cruise around a bit, slow down to a low rpm and run it up to high rpm, etc. Would this be a better way to tune the maf? Forgive me.....I'm new and learning! lol
When tunning anything airflow related you want to be steady state. No rapid pedal movements. And you want to filter out any transients that will give you bad data. What works for me when dialing in MAF is steady pulls up 5000 rpm from a rolling start in 3d gear. You should have maf sorted in an afternoon. Once you get it to around 3%, call it good enough and move on to VE. Your data will move one day to another because of weather changes, so i would no obsess over it. You can be spot on one day, and be +/- 3 the next. You can even get different results logging in the morning and then in the afternoon. The most important thing is to log with some filters and steady driving, otherwise you will spend weeks chasing your tail. I learned that the hard way, ha.
What types of filters help to best sort out this data?
Ultimately any that filter out decel, gear changes etc that will give you erroneous data. Basically 0% accelerator positions. You will find a bunch of good ones on this forum that you can just copy into your graphs if you search around. Thats what I did a while back when I first started playing with HPT. I will list some of the ones I use when I have access to my laptop later.
I've been searching and seem to be coming up light. I've setup and played with a couple of my own filters and still feel like in not getting much good data collected
Thank You
Thanks for this info it is helpful. I haven't looked at those filters yet, but do you use the filters to weed out the erroneous data while driving normally? Or do you also only log data while doing say a 3rd gear pull like you said? I assume throttle position doesn't matter, you can do wot or slower pulls to higher rpms? airflow is airflow, right? Doesn't matter how far open the tb is?
Thanks for all the help.
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