No, you have no control over the setup of the car. The only thing you can do is force intake restrictions on cars, but they have to pit in order for it to be updated. This means that, for example, you can give a car a 10% intake restriction via a command, but you will have to force pit them in order from that change to take effect. You can't modulate the level of restriction while the car is on track with the current tools we have as InSim programmers.
If you take a look in your LFS directory, you'll find another folder called docs. In that directory you'll find a file called InSim.txt. This contains all information about the InSim system, and what it can an can't do.
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I just want to say, I love what you're trying to do. I love F1 as well, and I wish you all of the best.
-- Mark 'Dygear' Tomlin, Founder - Simulation Federation Internationale de l'Automobile.