I completed it yesterday onboard a Toyota 7 ( B-spec).
I bought a 3rd phase Turbo to raise it's power, and entered the race.
After repeating it several times, I managed to win, here are some suggestions:
1) If on the front grid there are a Ferrari 330 P4, a Toyota 7 and a Ford GT40 all togheter, get out of the race and reload it, until there's just one or at last 2 of them, since they go very fast.
2)The Toyota 7 has a bad standing acceleration, so you have to already choose "speed up" before the green light, then immediately after choose "overtake".
3)Use "speed down" before you reach the chicane out of the tunnel, and before the last corner of the race (the one which connects you to the straight), in these 2 points your car or the others' tend to crash on the walls because of IA retarded mentality (they turn too much in advance).
Use "overtake" just after the first corner of the race. There the toyota goes fast enough to try an overtaking.