Early on so driving and tuning can improve but it's a good Starting point. Engine swap to GR.3 Z4, widebody, all aero parts
https://store.playstation.com/#!/tid=CUSA24769_00
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https://www.youtube.com/watch?v=yaIj7UMRQVI
Don't be nice because other players and the PD penally system will be evil, instead be even.
https://store.playstation.com/#!/tid=CUSA00572_00
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https://www.youtube.com/watch?v=4fOCbGnTQFg