Changing from LS3 to LS7 need guidance on setting up ecu for new engine

[Stubbs]

I have a RX8 that I swapped a LS3 into a few years ago. Long story short, I had an engine failure, and I am swapping the LS3 out for a LS427/570 crate engine from GM.
I was running the LS3 with a PSI Conversions standalone harness with a 2009 E38 ECU (service tag: 12625455 OS: 12628990)

I?m trying to figure out the most optimal way to run the LS7, and if that can be done with my current setup or if I need to change out to something different.
I?m only looking to have a base tune right now that will let me get a few hundred break in/shakedown miles done and then it will be final tuned after that.

My initial thought is to take my current tune file and use the compare log to move the tables from a stock 09 corvette Z06 over. I am a bit hesitant as the changes are extensive and I don?t know what, if any, differences there are between the OS in the Z06(12628988) I?m referencing and the OS in my current tune.
Reading through the forum there was someone who asked about doing something like this and it was advised against, but I'm not sure it was a direct comparison to what I was going to do.

Another option would be to just flash the entire 09 Z06 tune over. A couple concerns around that are that it would require using credits to license, which isn?t a big issue, but I want to make sure it?s the right way to do it before I spend the credits. I?m gun shy about doing that as I had a previous ECU bricked by a shop that flashed an incompatible OS.
Another issue with flashing the Z06 is related to the canbus, since the RX8 gauge cluster is canbus driven I had to use a converter to take the GM can data from the ECU and translate it to something the Mazda cluster could use. I ran into issues when getting it set up originally due to differences in the way GM handled the can data between ?08, ?09 and ?10 E38 ECUs. I can probably get it to work if it does become an issue, but I?d rather not repeat the experience.

Am I overthinking this? Is there a better way to approach this?

[10_SS]

I have a RX8 that I swapped a LS3 into a few years ago. Long story short, I had an engine failure, and I am swapping the LS3 out for a LS427/570 crate engine from GM.
I was running the LS3 with a PSI Conversions standalone harness with a 2009 E38 ECU (service tag: 12625455 OS: 12628990)

I?m trying to figure out the most optimal way to run the LS7, and if that can be done with my current setup or if I need to change out to something different.
I?m only looking to have a base tune right now that will let me get a few hundred break in/shakedown miles done and then it will be final tuned after that.

My initial thought is to take my current tune file and use the compare log to move the tables from a stock 09 corvette Z06 over. I am a bit hesitant as the changes are extensive and I don?t know what, if any, differences there are between the OS in the Z06(12628988) I?m referencing and the OS in my current tune.
Reading through the forum there was someone who asked about doing something like this and it was advised against, but I'm not sure it was a direct comparison to what I was going to do.

Another option would be to just flash the entire 09 Z06 tune over. A couple concerns around that are that it would require using credits to license, which isn?t a big issue, but I want to make sure it?s the right way to do it before I spend the credits. I?m gun shy about doing that as I had a previous ECU bricked by a shop that flashed an incompatible OS.
Another issue with flashing the Z06 is related to the canbus, since the RX8 gauge cluster is canbus driven I had to use a converter to take the GM can data from the ECU and translate it to something the Mazda cluster could use. I ran into issues when getting it set up originally due to differences in the way GM handled the can data between ?08, ?09 and ?10 E38 ECUs. I can probably get it to work if it does become an issue, but I?d rather not repeat the experience.

Am I overthinking this? Is there a better way to approach this?

It should be plug and play with minor changes the current LS3 tune if your reusing your injectors and coils. This would be mainly updating cylinder size in the tune.

Then:
If you can find a stock LS427/570 crate engine tune, you could copy the Fueling and Spark tables, I would take at least 5 degrees of timing.
You may need to increase Base Running Airflow for the bigger motor as it will need more air to idle (if your still using Electronic Throttle).
Then you may need to copy some of the Torque Model settings or you could have strange things happen to the throttle.
Knock Sensor settings from LS7 tune.
Transients from LS7 tune.

Also you may want to fine tune startup by looking at some of the LS427/570 startup airflow settings, if it doesn't start that great. I would not flash a new or stock LS7 tune to it, too much would be different (DTC's, etc).

[Stubbs]

Thanks for the advice!
Gives me a lot better idea of where to start from.
The LS427 came complete with injectors, coils and sensors. Should I swap over everything from my LS3? It appears the coils and injectors are the same between the LS3 and LS7 since they share the same appearance and numbers stamped on them. All the other sensors look the same except for the MAP sensor, I'll need to modify the LS3 sensor slightly to fit the LS7 manifold.

I'll have to do some digging to see if I can find a LS427/570 tune. I know GM sells a engine controller package for the swap, but it's E67 based. I might see if I can get it from them to at least look at, probably unlikely though.