I think it would be cool to have a checkbox with somethink like: “Build prototype” when building a new car or engine… For engines it would make all parts 25-35 % stronger (higher torque/RPM limits) but also way more expensive and of course disable mass production. For cars it would make the engine bay bigger (maybe also 25-35% more space) and the whole car/body a little bit lighter… This would allow us to build race cars and use really big engines (21.7L v16 ^^) just for fun (and exporting to beamNG drive). I think/hope this could be added without too much effort…
Alternatively it could unlock a higher qualtiy settings for engines, for example a maximum of +30 instead of +15
Edit: I’m talking about an option way stronger than the quality setting, maybe “overpowered” and unbalanced,
with the purpose of giving us a way to test out ideas or build race cars for beamNG… this could also be limited to sandbox only so it doesn’t mess with the balance in career mode