Hi,
Put this file in your Documents/Automation/Engines folder.
Open it in Automation.
Look at the settings and change the cam from 34 to 35 and see what happens.
Can someone explain? 
1.0L 16V DOHC Turbo cam 34.lua (58.4 KB)
output drops because the engine is knocking? your using premium unleaded so 95.0 ron is your limit…try ultimate unleaded instead.
The huge sudden change in RON. I don’t understand. Even if you keep raising the cam.
Also if you slightly change the size of the turbo, the same happens. I can’t figure out why this happens
There’s definitely something screwy going on behind the scenes, Jagermeister. It seems to be caused by the small air to air intercooler; with a medium or tiny sized IC, there’s no large step change in the octane requirement.
I tried it out, and yes, that must be a bug… which you can see much better when you back off on compression a bit so that things are not starting to knock. There is this huge step in RON there for some reason - we’ll investigate. Cheers!
It’s fixed now, will be gone in the next patch.
You’re welcome. Glad it wasn’t just me. 
Good find!