2007 C6 Z06 idle surge and bucking-New to me

I could use some help on a new to me car. It's a 2007 Z06. Unknown cam but it's healthy by the sound of it, was told "stage 3", heads were fixed/upgraded, full bolt-ons like intake and long tubes, NPP exhaust, etc. The car pulls hard, but the low speed/low rpm drivability is pretty lousy. It'll even surge or bump at speed at anything below 2000 rpms. This is my first time messing with an E38 ECU. I noticed the car is pulling max negative STFT's at low speeds so I'm putting a wideband on the car and redoing the MAF as the tune it came with is CL MAF only no LT's. The tune below is the existing tune with some tweaks that I made as the timing tables were commanding massive timing at low speed low RPM. It idle and drives better than before the changes I made, but still not great and the cold start is worse.

The OL tune I attached is the latest tune Im going to try while forcing the car into open loop. I've read through the below massive E38 idle tuning and still confused on some aspects about getting it to behave better.

https://forum.efilive.com/showthread...8-idle-tuning/

If anyone has thoughts on issues with the tune files or can highlight errors it would be helpful. Thanks in advance and I know I need some longer/better logs, but this is what I have for the moment.

Here are some logs from the above OL tune that also matched the min idle airflow with what the MAF was measuring....surging/bucking was significantly better while driving. You'll see some surging still on a cold start log (file number 3) and there's a slight oscillation on the warm idle (log number 4). I was playing with the adaptives in log number 4, but it's definitely something in the idle tune related to spark as you can see the drops in timing. Some input would be appreciated. I'm going in the right direction, but looking for some help.

Bump....any help?

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Originally Posted by ddnspider

Bump....any help?

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This forum doesnt have much traffic on it anymore.

Have you tried MAF OL?

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Originally Posted by nonnieselman

This forum doesnt have much traffic on it anymore.

Have you tried MAF OL?

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OLMAF helped. I've made huge progress. The car has WAY too much timing in it and not near enough min airflow. But there's still more work to do. I've been trying to read up on EOIT and think I need to move that around but unsure how or by how much. And then I added an airflow straightener to the MAF and need to get a wideband on the car to redo the transfer function.

Attachment 24693Attachment 24694
Latest tune and log. Idle is rock solid now, but still getting a trailer hitching feeling at low rpm (1200-1800). Could really use some tips on where to look to fix this.