The Strega looks decent and would be a great alternative to an MX-5 or S2000. However, a 2-valve/cylinder DOHC head would have been more fitting for the 60s and 70s - it would be very outdated for the 1990s, let alone the 2000s. As for the Giove, I remember the 4-door version from QFC8, where it was quickly found wanting:
TRX tires are those with a diameter divisible exactly by 10 (an attribute shared with racing tires) - so why on Earth did you use them? It may have been that the rule set did not say anything about them.
Keep doing these challenges bro, especially the QFC ones since they have quicker turn around times. You will learn a lot, and every car you will improve. The learning curve is fucking HUGE with this game, so many different aspects.
Your suggestion deserves a separate thread all by itself - this one is not really the right one to bring it up. Besides, fulfilling one of these requirements is easy enough, but meeting all of them at once would be a tall order, to say the least.
I had only played this game for a couple of weeks when I made that car.
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