Bumpers, that is still true but that is becoming more untrue with each update since they would often interfere too much with people’s stylistic visions.
Also, the size and position of wings, lips, and spoilers in the game is what sets the maximum available downforce on each part of the car. If spoilers were not responsible for this, that means it would have to be included in the UI somehow, and the devs have been working to eliminate UI clutter as much as possible. Making it a UI element would also likely mean imposing some kind of arbitrary limit whereas with the current system, the limit is fully dynamic.
A version of what the OP suggests might be interesting. After all, companies spend thousands of hours making subtle aerodynamic tweaks to their cars, not just to reduce drag, but also to change front and rear lift values to aid high-speed stability (amongst other things).
From that point of view it might make sense to be able to tweak car aero without fixtures just to reduce lift, not to a point where you can make any actual downforce.
Yes, is should clarify. I was trying to say, as the OP did, that maybe you could have acertain amount of aero adjustment available without fixtures (but not enough to give negative lift i.e. overall downforce). This range of adjustability could then be increased by adding fixtures.
except it doesn’t. I routinely put a vertical spoiler hidden in the rear bumper to avoid the ugly double spoiler on some models, like the compact suv, should be just drag at most but works just fine.
tu quoque?
there’s plenty
but that’s beyond the point. the point is setting spoilers is as pointless as it was linking available cooling to the grill fixtures
Not quite pointless as size, position, and number of aero fixtures all have different effects, whereas cooling was just a cumulative value of cooling fixtures regardless of where they were placed. For cars with that little spoiler includes, adding a lip to the back or another spoiler on top will give the same effect. Most of those things on production cars are meant more for aesthetic than providing downforce anyways.
You’re misunderstanding the mechanics of aero fixture placement.
Yes, aero fixture placement way not work entirely realistically but it does still contribute to maximum downforce on each part of the car. The game only cares about the forward-backward placement of the fixture and its size and that is both for aesthetic freedom and also because trying to accurately model aerodynamic forces is beyond the scope of Automation.
Those don’t create meaningful downforce like Daffyflyer said above. They are just there decrease the effects of lift, unwanted turbulent air, and decrease the coefficient of drag (like NASCAR). A wing on the other hand creates downforce for more grip around corners and increased drag (like open wheel, GT racing). Also a little bit of design features are just there for looks like fake grills, hood scoops vents, and spoilers.