I was thinking about this. Let’s just say that with the right power restrictions, having too much aero on a Tier 1 or 2 car would be merely disadvantageous.
I do agree that to mimic the conditions of the games, each tier could come with a boost limit on any turbo. Say, 0.6 bar for tier 1, 1.0 bar for tier 2 and unrestricted for tier 3, but, again, if anything a hybrid of power to weight ratio and power limits would actually mitigate all this.
My suggestion to android earlier was to try this:
Tier 1: maximum 200hp:ton or 200hp whichever is lower
Tier 2: maximum 400hp:ton or 400hp whichever is lower
Tier 3: maximum 600hp:ton, but no absolute maximum to power.
I was also going to suggest that only tier 3 cars can convert drivetrain type (to AWD). Even at 600hp:ton, a well tuned, lightweight car will actually still be faster RWD than AWD if the weight distribution is favourable.