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hquick
March 9th, 2008, 02:01 PM
Hi All,
As the MAF table is tuned via 'paste/multiply' is it then possible to tune it using RTACS? Same way as it is done with the Auto VE tuning?
What filters should I use and what cell count is reasonable?
Thanks

Howard

Here's a tune I ran this morning and a resultant tune using the paste/multiply method (not RTACS) after applying a log.

Highlander
March 9th, 2008, 03:45 PM
you would have to disable LTFT and STFTs for it to work... you must have a wideband... use the Calc.Ben PIDs and you should be able to do it.

hquick
March 9th, 2008, 04:16 PM
Thanks....I'll give it a try.

Howard

TAQuickness
March 10th, 2008, 08:07 AM
Would be most nearly identicle to the concepts applied to VE tuning. The big difference is you are tuning the MAF table instead of the VE table.

I don't have a MAF to test with, but I would imaging the same RTACS filters used for VE would apply for the MAF as well.

Because the MAF table offers a higher resolution than the VE table, you may want to make your fine and course adjustments a bit more subtle to avoid skewing the MAF table with transients.

hquick
March 10th, 2008, 10:25 AM
Here's the log, before and after tunes from this morning.

hquick
March 10th, 2008, 08:25 PM
OK...in trying to tune the MAF using RTACS...it seems some area's just will not pull into line.
I'm in the 14.7 (stoich) area's of my commanded AFR and I'm seeing 1 AFR rich at alot of points.
Question:
If the IFR table has been altered to richen up the mixture globally, will this cause the situation I describe?
I'm goinmg back to the settings from my OLSD Auto VE tuning and will give it another shot.

hquick
March 10th, 2008, 11:52 PM
OK...is the fact that I'm seeing LTFT's of -1.6 what's skewing my MAF tuning (seems to be staying rich)?

http://img.photobucket.com/albums/v35/hquick/datatab.jpg

Thanks

hquick
March 11th, 2008, 11:00 AM
This morning I reset the trims and went again.
Better results.

TAQuickness
March 11th, 2008, 11:37 AM
You should have fuel trimming disabled while you tune your airflow tables.

hquick
March 11th, 2008, 01:25 PM
Thanks TAQ yes I have got it disabled...however I hadn't reset the trims and so iut seemed they were still affecting it as they were sitting on -1.6
After zeroing them this morning...ben's seemed to fall into place alot better.

hquick
March 11th, 2008, 04:41 PM
Well...I'm getting there.
Here's my MAF correction table after RTACS this afternoon.

http://img.photobucket.com/albums/v35/hquick/MAFtable120308.jpg

TAQuickness
March 11th, 2008, 08:24 PM
WOW! That looks really good!

hquick
March 14th, 2008, 01:39 PM
OK...Here it is as of today.
We're experiencing some really hot weather 41oC yesterday and what "ive noticed is....after a run in cooler weather (3am and deserted freeways so any speed...more the slower speeds actually...constant throttle and watching the scantool sit in cells until they hit 1.0) if I shut it down for a few hours and come back and restart it.....I get lean readings again???
Any idea's?
I'm thinking ECT's have risen or IAT's???

http://img.photobucket.com/albums/v35/hquick/MAFtable150308.jpg

Highlander
March 14th, 2008, 04:07 PM
it may be due to many MANY things.. I am sure you can never hit them 100% all the time.. even at the same temp... so many different conditions.

It gets to a point where it doesn't matter if its dead on. Want it dead on.. use the O2s... otherwise.. Driveability is the most important aspect of tuning.

Stoichiometric
March 16th, 2008, 03:56 AM
Howard,
Your MAF trims are looking very good. I would disable the MAF now and work on the VE for a session. Once the VE is getting close re-enable the MAF and see where you stand. My B3601 is set at 14.68, that may help just a little bit.

hquick
April 3rd, 2008, 07:21 PM
Re enabled the trims and immediately goes very lean?