What adjustments are needed to the tune post long tube header install

Like title states, Truck is 2000 Silverado w/ 5.3 swap, had tuned with shorty's and cats on it. I have installed long tubes with off road y -pipe and high flow muffler. I have the MPVI3 with a AEM wide band installed. I am just looking for some help with what adjustments I need to make to the tune and what road test to perform and what to watch for when adjusting for the added flow of exhaust. I believe @WOT It will be lean??? So was thinking of adding some fuel in the VE table from 5500 to 6500 just to see where I'm at, but need help on what I need to look at when reviewing the data log. Please give me some sort of direction here, I have dropped a lot of money on my software and hardware and I am struggling to make little adjustments, my intention was to swap the truck have it professionally tuned with it just being camed , and add little things after and adjust the tune little by little. Thank you all, have a great memorial weekend.

The first item on the to-do list is to install the wideband. You say that is done, so next you have to get it to read accurately in the scanner. If serial input is an option with the AEM you bought (it is not on some newer ones), then use that to input to hptuners. That eliminates having to account for any possible voltage offsets with the analog inputs. On later models you can use canbus input, but I don't think that is an option on non-canbus vehicles (I don't have an mpvi3, so?). Once you have ACCURATE wideband readings coming into the scanner, you need to set up the channels you wish to log in order to get the % difference between commanded and actual fueling. This will involve a lot of reading to learn what you need to set up. While doing that research you will likely come across the info you need to determine how to adjust the VE and MAF tables appropriately. It will seem like a lot of info at first, but it gets easier. DON'T blindly make changes that you don't fully understand without having data logged first. Just installing a set of headers is not going to make enough difference to blow your motor while you are gathering data, so you have a best case scenario for being able to learn tuning.

Having tuned a bunch of them, will need a small bump to the VE table almost globally if not globally. Good starting point is to add 5% across the board by multiplying the whole table by 1.05 before driving it and fine tuning. The other thing that will likely need to be adjust watching data is the Integrator Delay time. Leave it stock for the 1st trip. Increase Integrator Delay by 1.1 repeat. Somewhere between 1.2 and 1.4x the factory value usually gets the 02s cross counting about like factory again. With the offroad Y this is more to help prevent engine surging from the 02s being further down the pipe and more exhaust volume in front of them.

I have some more info for you all so that you guys can assist me better. The truck has already been Dyno tuned. Post the dyno tune I have installed the long tubes and y pipe ( no cats). All of the VE and MAF is dialed in, how ever this was all done when the truck had factory exhaust( shorty headers , cats ex..). The wide band is installed and my tables are setup on the VCM scanner. I have seen that there are some settings to O2 under exhaust. So when road testing, 1. What do I look for?
2. Since the truck is already Dyno tuned, do I need to just disable MAF and only tune for WOT in the higher RPM due to the more free flowing exhaust?

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Originally Posted by GMTECH704

I have some more info for you all so that you guys can assist me better. The truck has already been Dyno tuned. Post the dyno tune I have installed the long tubes and y pipe ( no cats). All of the VE and MAF is dialed in, how ever this was all done when the truck had factory exhaust( shorty headers , cats ex..). The wide band is installed and my tables are setup on the VCM scanner. I have seen that there are some settings to O2 under exhaust. So when road testing, 1. What do I look for?
2. Since the truck is already Dyno tuned, do I need to just disable MAF and only tune for WOT in the higher RPM due to the more free flowing exhaust?

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You need to log some data to know what it needs. And for anyone here to answer your question you would have to post the current tune with a log. A "dyno tune" means very different things to different people. It could be a full range tune that properly altered every needed parameter, or it could be someone just raped the PE table and bumped up spark to make a dyno number. You can say the VE and MAF were dialed in, but we have learned to not just take people at their word on that sort of thing.

Just start logging. It's not going to make some tremendous difference where you need to make a preemptive change.

Unless maybe this was a cammed truck and now it has headers. Even though.. just start logging and making adjustments.