[Juho]

It goes to around lambda=1.12-1.14 at low load, because of the load cells.
But maybe with changing the load values I can get it work and try lambda=1.05-1.10 at low load.. and a bit leaner at medium load.

Edit: looks like I'm already running now lambda=1.25 at 100km/h ~flat roat.
Only luck, since I had at some point modified the throttle body map to open 0.5% at 10% TPS. There is some pedal movement allowed, only thing that changes is how much air the engine gets -> afr goes leaner slightly (from about lambda=1.20 to 1.25) if I press only slightly more throttle.

At lower speeds I have some work to do, so I could achieve the lambda=1.25

I'll try to find the limit where it starts missfiring or is too sensitive for missfiring.. but before that I drive the whole week with current ecu file so I can actually see if it's any good.
Did some minor afr and ignition timing optimizing.
And if my thermostat arrives next week, I test how it works with higher temperature.

The ignition timing maps do look quite different than with the catalytic converter headers.
Quite a lot less advance required for the ~same fuel consumption.