It'll only take, what? 2 minutes to win a race, even if you go with the long course. 4x2 = 8x4 classes = about 32 minutes maybe? The races will take less time as you go up in rank though, since the birds are faster. About a half hour I would say, depending on your bird.
All work and no play makes Jack murder his whole entire family with a god damn axe - cumbojumbo
First, what course you select has no baring on gaining a rank, short or long, the win is all that counts. Win three races and you go up a rank, they don't have to be in succession, just win three, and bingo.
Second, you don't need to get all your chocobo's up to S rank to get a gold chocobo, you only need a set of combined wins between each parent to guarantee success.
Between the great/good you need 4 combined wins to get either blue/green Between the blue/green you need 9 combined wins to get the black Between the Wonderful/Black you need 12 combined wins to get the gold (providing you select the black first, game glitch).
Now these are combined wins, meaning that if you race your great chocobo and win 4 times, you don't need to take your good chocobo to the track because you will have exactly the same chance for a blue/green (50% on each) than if you raced them to S class.
Just because you claim to be honourable doesn't mean you are. GT - Sniper Fox29.