Tuning the "Closed Loop Integrator Delay" After Installing Headers

NG329 · 07-26-2022, 06:46 AM

Hey guys,

I'm trying to get my current tune in the ballpark before I head back to the dyno. Getting an appointment is pretty tough.

I recently installed Long Tube Headers on the ZL1 and I know that since the Oxygen sensors are further away from the manifolds it can skew the readings. For those of you who tune with HP Tuners, where are you setting the "Closed Loop Integrator Delay" after you installed the headers.

Stock is:
ms 0 8 16 24 32 40 48 56 64
Delay 1200 471.875 383.125 311.75 203 163.25 146 129.25 98

As an experiment I set it to:
ms 0 8 16 24 32 40 48 56 64
Delay 1800 707.75 574.75 467.625 304.5 244.875 219 193.875 147

It cleaned things up a little but I only went 50% more on the adjustment. I've heard that you could even double it or triple it. What have you guys found success with.

I also lowered the proportional limit by 25%. it was 2.000 and I set it to 1.500

Any advice is most welcome.

NG329 · 07-26-2022, 07:05 AM

Also, contrary to conventional wisdom, it seems that after installing the headers and removing the CATs the car is running rich. My exhaust tips are BLAAAAAAACK! Full throttle was breaking up over 5,000rpm.

Any suggestions on how to resolve with MAF tuning?

Joshinator99 · 07-26-2022, 08:39 AM

Quote:

Originally Posted by NG329

Also, contrary to conventional wisdom, it seems that after installing the headers and removing the CATs the car is running rich. My exhaust tips are BLAAAAAAACK! Full throttle was breaking up over 5,000rpm.

Any suggestions on how to resolve with MAF tuning?

You can do idle and part throttle MAF tuning using the OEM narrowband O2s but will need a wideband to tune WOT. If you’re not familiar with the process, you’ll probably be best waiting for your tuner to iron it out for you.

6spdhyperblue · 07-26-2022, 09:57 AM

Quote:

Originally Posted by NG329

Also, contrary to conventional wisdom, it seems that after installing the headers and removing the CATs the car is running rich. My exhaust tips are BLAAAAAAACK! Full throttle was breaking up over 5,000rpm.

Any suggestions on how to resolve with MAF tuning?

You have an exhaust leak

KingLT1 · 07-26-2022, 10:02 AM

The tips are black because you removed the cats and running pump gas. The delay setting your messing with is doesn't matter much if the other parts of your tune are off. I have tuned a few header cars and they seems to run fine without messing with that integrator delay. I would check for exhaust leaks near the o2's but There is a lot more that needs addressed in the tune.

NG329 · 07-26-2022, 10:22 AM

There's definitely no exhaust leaks. We welded everything instead of using clamps. I'm positive there are no leaks.

I'm running a mix of gas and Ethanol. The changes I made cleaned things up a bit but just wanted to be certain before I head to the dyno.

6spdhyperblue · 07-26-2022, 10:30 AM

Quote:

Originally Posted by NG329

There's definitely no exhaust leaks. We welded everything instead of using clamps. I'm positive there are no leaks.

I'm running a mix of gas and Ethanol. The changes I made cleaned things up a bit but just wanted to be certain before I head to the dyno.

You welded the headers to the mid pipe? There’s something wrong somewhere. Maybe a plug then. The tuning isn’t doing that

Would hate to lose a day on the dyno because of an issue like this

NG329 · 07-28-2022, 06:19 AM

Update:

I raised the integral delay even further and lowered the limit to 1.2 and things got cleaned up a lot.

The only thing I notice now are that 5th and 6th gear could be a little peppier and according to my logger the idle is rich. Everywhere else the LTFT is pretty happy.

6spdhyperblue · 07-28-2022, 01:45 PM

Let us know how it goes on the dyno

cmitchell17 · 07-28-2022, 08:03 PM

My only diy/cheap way I could think of doing it would be to get a wideband in the stock O2 location and just read on the log the time it takes to respond from steady state, then add its specified response time to that. I think on mine I remember maybe around a 200ms time, but I can't really remember and I don't remember the values in that integrator delay table, but I don't actually think they are coefficients of the PID controller but the response or rise time.

07-26-2022, 06:46 AM	#1
NG329 Drives: Chevrolet Camaro ZL1 1LE Join Date: Oct 2021 Location: NY Posts: 702	Tuning the "Closed Loop Integrator Delay" After Installing Headers Hey guys, I'm trying to get my current tune in the ballpark before I head back to the dyno. Getting an appointment is pretty tough. I recently installed Long Tube Headers on the ZL1 and I know that since the Oxygen sensors are further away from the manifolds it can skew the readings. For those of you who tune with HP Tuners, where are you setting the "Closed Loop Integrator Delay" after you installed the headers. Stock is: ms 0 8 16 24 32 40 48 56 64 Delay 1200 471.875 383.125 311.75 203 163.25 146 129.25 98 As an experiment I set it to: ms 0 8 16 24 32 40 48 56 64 Delay 1800 707.75 574.75 467.625 304.5 244.875 219 193.875 147 It cleaned things up a little but I only went 50% more on the adjustment. I've heard that you could even double it or triple it. What have you guys found success with. I also lowered the proportional limit by 25%. it was 2.000 and I set it to 1.500 Any advice is most welcome.

07-26-2022, 10:02 AM	#5
KingLT1 Drives: 2016 1SS NFG A8 Join Date: Aug 2017 Location: 46804 Posts: 6,799	The tips are black because you removed the cats and running pump gas. The delay setting your messing with is doesn't matter much if the other parts of your tune are off. I have tuned a few header cars and they seems to run fine without messing with that integrator delay. I would check for exhaust leaks near the o2's but There is a lot more that needs addressed in the tune. __________________ 2016 NFG 1SS A8 Options-2SS Leather/NPP Perf. mods-Whipple 2.9/Fuel System/Flex Fuel/103mm TB/Rotofab Big Gulp/Cat Deletes/Corsa NPP Per. times- 10.5 @ 137 w/ 1.8 60ft Full weight on 20's 1200DA

07-28-2022, 01:45 PM	#9
6spdhyperblue Drives: 6th gen Join Date: Aug 2013 Location: US Posts: 3,675	Let us know how it goes on the dyno __________________ ‘22 2SS 1LE M6 Summit White - RF, Flexfuel, LT2 intake, 95mm tb, ATI udp, VT ramair, full 28” dragpack - 11.68@122 ‘16 1SS M6 LT2 intake + boltons on DR 11.0@126+ (Sold)

07-26-2022, 07:05 AM	#2
NG329 Drives: Chevrolet Camaro ZL1 1LE Join Date: Oct 2021 Location: NY Posts: 702	Also, contrary to conventional wisdom, it seems that after installing the headers and removing the CATs the car is running rich. My exhaust tips are BLAAAAAAACK! Full throttle was breaking up over 5,000rpm. Any suggestions on how to resolve with MAF tuning?

07-26-2022, 10:22 AM	#6
NG329 Drives: Chevrolet Camaro ZL1 1LE Join Date: Oct 2021 Location: NY Posts: 702	There's definitely no exhaust leaks. We welded everything instead of using clamps. I'm positive there are no leaks. I'm running a mix of gas and Ethanol. The changes I made cleaned things up a bit but just wanted to be certain before I head to the dyno.

07-28-2022, 06:19 AM	#8
NG329 Drives: Chevrolet Camaro ZL1 1LE Join Date: Oct 2021 Location: NY Posts: 702	Update: I raised the integral delay even further and lowered the limit to 1.2 and things got cleaned up a lot. The only thing I notice now are that 5th and 6th gear could be a little peppier and according to my logger the idle is rich. Everywhere else the LTFT is pretty happy.

07-28-2022, 08:03 PM	#10
cmitchell17 Drives: 17 2SS, 8L90, Cam, Heads, E85 Join Date: Dec 2016 Location: US Posts: 1,201	My only diy/cheap way I could think of doing it would be to get a wideband in the stock O2 location and just read on the log the time it takes to respond from steady state, then add its specified response time to that. I think on mine I remember maybe around a 200ms time, but I can't really remember and I don't remember the values in that integrator delay table, but I don't actually think they are coefficients of the PID controller but the response or rise time.

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