I guess as a work around I could unplug the rear 02 and disable the dtcs, that will ensure it has no influence at all on anything Yes, we actually do this on some cars, especially on those which we cant to use leaner mixture for cruising and low loads. With the secondary O2 still connected you can'...

Ok, I just saw you posted a log, but why would you use forscan to get it when you have versatuner?! Download the attached dashboard preset, open your versatuner go to Dashboard -> presets -> import and then load the newly created preset. Then take a WOT log in 3rd gear from 3000-ish to 6000-ish rpm ...

Do you have any idea where is the problem?do you want a log? Yes, add a log. Also my car has fmic(max 450hp), tial qr, hpfp autotech internals, 1 step colder plugs with 0.7mm gap, 76mm downpipe 200 cell cat, 70mm custom exhaust, custom intake (oem diameter) and custom tune. In my log with 3rd gear ...

That does not right to me, every other vehicle I have tuned uses rear 02 sensors for long term fuel trim calculations. Every manufacturer have their own approach on things. But to be honest I do not think that any of them use the secondary O2 (post-cat) for any sort of fuel trims readings (I'm only...

Removing the catalytic converter will not affect the fuel trims in any way, the primary O2 sensor is before the primary cat.
You can disable fuel trims entirely but I do not see how this would be a good idea.

It's the same as on any MPS. These turbos have a 8PSI spring in the wastegate so the crack pressure should be around that, but it really depends on various things (how freely everything moves on the turbo, if the boost source line from the turbo compressor housing is intact or has some wear/kinks). ...

The V1 may not be able to make 500 or that's where it will stop in a very optimistic scenario, but in your case the limitation will be the factory fueling system unless you decide to go with aux fueling. A WMI kit from snowperformance is around 1000EUR with everything you need, so shipped to the UK ...

If yours doesn't smoke then it's good. But of course the BNR will bring a lot more joy in your life...

dickyB wrote: ↑November 3rd, 2025, 7:19 am I’m away working and was wondering if anyone has a suitable map or can make a base map as a starting point, thanks

The BNR S4 v1 is pretty old, probably like 2015-2016, they are pretty rare these days. Are you sure it's an S4 v1?

Ok, so the logs you posted with idling look relatively fine. However after looking at the tune I have to admit that this is by far the worst ever MAF calibration I have ever seen, ever. Worst-MAF-CAL-ever-20251005.png By comparison this is how it should look like: SomeRandom-MafCal-20251005.png You ...