Yes, there are lots of tuning options.
Drive train tuning, suspension tuning, aero tuning (on some), brake tuning, etc all on the Garage screen.
I rather suspect what you're talking about is modifications though, not tuning. Tuning is taking what you have and changing it to perform differently.
For example, when I tune my guitar, I don't whack on big pieces of plastic and tin (and filler, always plenty of filler) because that doesn't make it sound better.
Heeeeere we go!
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Modifying the cars is pointless. Eventually, people would work out the ideal setup for each track and car and everyone would use it. Look at the number of people who use Inferno setups if you need proof that it would happen.
Therefor you end up with a field of identical cars, and guess what? That's exactly what we already have.
So how about you just drive the cars you have and I dunno, bang a metal trash can lid with your face to simulate the noise of a pointless "masseev zorst!!1111"
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