so, i've started the championship in A-Spec, with my 2010 Dale Earnhardt Jr. #88 Impala . i've only changed the oil when i won it, then i have done 21km with it and then changed the oil again (before the champioship) and the car as 879hp.
1st race: finished 1st with -14.544 (just slow down to 280km/h to make the turns, easy as pie)
2nd race: in the end of the 1st lap i was in 3rd, (lost control in 1st turn to last place, and lost control in the sharp corner to the tunnel getting to 8th place, both ending up in the sand), then in the 1st turn of the 2nd lap i got in 1st place

finished 1st with -16.694
3rd race: end of 1st turn = 1st place, finished 1st with -13.590
4th race: end of 3rd turn = 1st place, the AI drivers break almost to 0km/h in the last corner, so you get a lot of time with that turn, finished 1st with -21.510
5th race: guess what? Last place... Yes... i make it to 1st place in the 1st lap, but they will manage to get you by the 2nd lap, then in the begining of the 4th lap, one of the ***k*ng idiots made me spin, i have managed to get right away in the right direction, but i have slowed down to 200km/h... i have managed to recover 0.200 per lap, but it's not enought as the car only gets to 360km/h. finished with +2.787
SO ALL I HAVE TO SAY IS: ATENTION TO THE AI DRIVERS AS THEY WILL NOT GET OUT OF THE DRIVING LINE, THEY WILL KICK YOUR A**...
2nd try of the 5th race: I have made the gear ratio to 400km/h (maybe not a good idea, as it takes more time to get to max speed), then i have made a strategy, in the turns, get by the inside the closest of the yellow line as possible, in the big part, just get out of the front of the cars, get between the grass and the yellow line, with this the AI Drivers will not catch you soo fast; in the small turn (finish line), as you get off the last turn, just get in front of the other cars, so that they can't pass you. only 2 have managed to get in front of me, but by a small distance, that you even can't see... they will get behind you in the turns... the most intense race that i've done, Nascar it's out of the way for me, next: Formula GT :S
EDIT: in the end, my car it's with 895hp... and i've won a car that doesn't match the dificulty level of the damn championship!!! (as usual -.-'')