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