Here is the full list of all 29 Slipstream achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Complete everything.
Complete all possible routes in Arcade Mode.
Defeat every rival character in Arcade Mode at least once.
Defeat Norman in Parthenon.
Defeat Tofu Boy in Akagiyama.
Win a cannonball race of all 5 secret tracks, in any order
Win a cannonball race of all 5 nighttime tracks, in any order.
Win a cannonball race of 15 tracks.
Win all the races in all cups.
Win the Diamond Cup.
Win the Emerald Cup.
Win a race in Grand Prix mode without any car upgrades.
Reach every exit defeating all the rivals along the way.
Defeat all the rivals in a cannonball race of 5 or more tracks.
Visit all the tracks in Arcade Mode.
Get to all the exits in Arcade Mode.
Defeat Camilla in Highgate Cemetery.
Win the Sapphire Cup.
Win a cannonball race of 5 or more tracks.
Stay on the slipstream for more than 15 seconds in any mode.
Win a battle royale match.
Win a race with every car model in Quick Race Mode.
Defeat all the rivals in a single Arcade Mode run.
Defeat David in Neon City.
Complete a stage in arcade mode without touching anything.
Defeat Alex in Metropolis.
Win all the races in any cup.
Win the Ruby Cup.
Get to the finish line in Arcade Mode.