The Yellow Light of Death and B-Spec Grinding

Recently, I've gotten back into playing Gran Turismo 5. Previously I ended up getting bored of it due to the fact that there wasn't much to do, compared with other versions of the game and that in-game money was a pain to get by due to the lowered prize totals in many of the races. I still recall having to play through the race on the Indianapolis Oval in the "American Championship" event repeatedly when they temporarily doubled all prize funds last year. Or was it the year before last? (Can't remember...it was that boring...)