Pagani Zonda is the best, you do not need nitro to get 8.2 with nitro 8.0- then tuning=7.8
best way to understand how to drive you car -
go to | race -> friends -> race ->
then choose distance, level, and you will see exactly where is your slow moments...
this way i found how to speedup my zonda even without tuning/
i start with 2nd, then 3rd on 7K, 4rth on 7K-7,5K push nitro and gear together, and same with 5 to the end.
6th gear you push only for 1/2mi