Help with airflow tables, Please!!!!

[DWS6]

I have a small problem that just needs a little adjustment. I have done extensive research using search so I need some straight forward answers.

The car idles really well, all mods are in sig. I rescaled the MAF but did not really mess with the VE other then dropping the 400, 800, 1200 rows 3%, 5%, and 10%. LTFT are positive 5-6% at idle and go up to around 8-12% at cruise and 0 at heavier loads and negatives on decel.
The problem is the rpms hang a little between shifts and when you let off the gas while cruising around 2000-3000 rpm. It doesnt stay at any particular rpm for any length of time just decelerates slowly. I am pretty shore this is airflow related but I don't know what table. I am using EFI Live.
Also when slowing down at a light or coming off the throttle quick the rpms drop to about 600 but then come right back up to 800.
What table to adjust this?

Also how should I go about getting the LTFT down at idle? I did just reset them. STFT are low 0-2% but the LTFT climb as time goes on (a couple of miles).
Do I just let them go for a while and see where they end up before trying to adjust?
Thanks,

[Chris81]

Do you have a wideband on the car? You should really autotune the VE table to get it straight (you can use the custom operating systems to build a boost VE table as well). I think you can only use this OS MAFless though (not positive)..

And/or you can also autotune the MAF the same way to get it lined out AFTER the VE is corrected.

Also, you need to build a map and log the RAFIG PID to get your desired airflow inline. That should take care of some of your airflow problems..

I would try this stuff first, then see where you are. I've been tuning a friend's stroker Vette with ETC and a big cam and these things made a huge difference.

[DWS6]

Yeah I was just reading your post on that. What is the RAFIG pid. Did not see that in the list of PID's. I don't want to get into a custom OS just yet. And I want to stay with the MAF as well. I am still very new to tuning so I am just trying to keep things as simple as possible until I get a handle on it.
I do have a WB. Can you elaborate on building the map for Running Air Flow?
What pids?
Thanks for responding.
Dave

[Chris81]

There should be a calc PID that says RAFIG (IG for in gear), this PID adds the short and long term idle trims together..select this PID. You will have to select IAC_LTD_DMA (long term) and IAC_STD_DMA (short term) for the RAFIG PID to work as well.

You will need to build a map to plot this info..

Go to your maps and hit Ctrl+Enter to make a new map.

Here you need to set up everything..

Data: select RAFIG for the parameter
Column: select engine RPM for the parameter and for col labels use "In Gear"
Row: select Engine coolant temp for the parameter and then go to your Desired airflow table (B4307) and click in the top left corner and copy with labels, now go back to the row properties and click "Paste labels" and it should put in all the temp values for that table for you.

Now save it and it should work.

Also, it is important that you make sure the units in your calibration and the units on the table in the logger are the same. (most likely g/s)

When logging for this, let the car sit overnight so it is cold and fire it up already recording, you want to let the car warm all the way up and let it sit for a bit idling (a couple of minutes) after warm to get a good avg. for whatever temp it stays at. (use the average of all the data)

Your new map should show some numbers, either + or - in the blanks. This is how much you need to add, or how much to take away from your desired airflow. So, just click the top left of the map and copy with labels.. then go to your B4307 in the cal. and paste and add and that should be your new desired airflow.

There is also alot of good info in the "idle transition" thread as well you should check out

I had a hard time figuring all this out, so now that I did I figured I could type it out for anyone that is having trouble so it isn't such a pain for a newer tuner (i'm still sorta new too)

Hopefully I didn't forget anything..lol

Chris

[DWS6]

Cool, I did not see the RAFIG pid but I will check again.
So the Running Airflow is the same as Desired Airflow? I think I remember seeing a pid for Desired Airflow. Could this be right?
Thanks alot bro, I will give it a try tonight.

Dave

[TAQuickness]

in the PID selection, uncheck the supported box if it is checked. You can filter for calculated PID's as well for easier searching.

[Chris81]

Cool, I did not see the RAFIG pid but I will check again.
So the Running Airflow is the same as Desired Airflow? I think I remember seeing a pid for Desired Airflow. Could this be right?
Thanks alot bro, I will give it a try tonight.

Dave

Yes, Desired and Running airflow are the same thing.

[DWS6]

Thanks alot, I tried some tuning last night and dialed the RAF in per your steps above. I then tried tuning the cracker and follower tables (-.4 on both) so the rpms would come down a little faster between shifts and to get rid of some of the cruise control effect. I think it helped but I need to drive it again tonight when I get home if its not raining. Am I doing this correctly? Do I subtract from the table? I think the car is seeing to much air hense the cruise and the slow decel between shifts. Am I thinking of this correctly?

Thanks,

[Chris81]

You want to subtract from the delay and decay tables to get it to wait longer before it reacts or vise versa and reduce airflow if the idle is hanging or add if it is dipping.

It sounds like your on the right track.. keep reducing airflow by percentage until the hanging idle/transitions are gone.

[DWS6]

Worked like a champ. Drives almost like stock, thanks a lot for your help!

I have a little bucking in 1 st gear around 1000 rpm but I think it just might be a characteristic of the cam, Any thoughts on this?

[Doc]

Autotune your VE table. I bet you find a lean condition in the cells that are bucking.

[ringram]

Also timing might help too

[Chris81]

Worked like a champ. Drives almost like stock, thanks a lot for your help!

I have a little bucking in 1 st gear around 1000 rpm but I think it just might be a characteristic of the cam, Any thoughts on this?

No prob..

Like the other guys said.. autoVE and get all the fueling right and try adding some timing using the live controls so you can see how much it needs in real time.