There are several vehicles and categories of machines you can unlock in Ridge Racer 3D for the Nintendo 3DS.
You’ll unlock new categories as you progress through the game, but the only unlockable cars are special category 1 machines. Good luck, because unlocking those can be pretty tough.
Unlockable Machine Categories
Category 3 Machines – Finish Beginner Grand Prix Event 08
Category 2 Machines – Finish Beginner Grand Prix Event 18
Category 1 Machines – Finish Advanced Grand Prix Event 26
Unlockable Category 1 Cars
Age Solo Petit500 – Finish Expert Grand Prix Event 44
Kamata ANGL Concept – Finish Expert Grand Prix Event 42
Lucky & Wild Madbull – Finish Expert Grand Prix Event 45
Namco New Rally-X – Finish Expert Grand Prix Event 47
Namco Pacman – Finish Expert Grand Prix Event 46
Soldat Crinale – Finish Expert Grand Prix Event 43