Engine Classes are the key gameplay mechanic in the Mario Kart series, similar to difficulty levels in other games. In Grand Prix mode, the player must select the engine class he/she wishes to compete in. The higher the engine class, the faster all karts go, and the more aggressive the AI racers are. There are four engine classes in all: 50cc, 100cc, 150cc, and the unlockable Mirror Mode, which is only available after getting a gold trophy in every 150cc cup. In Super Mario Kart, 150cc is only available after getting a gold trophy in every 100cc cup.
At 50cc, the AI racers do not drift much and rarely performs Mini-Turbos. Most will spin out on the starting line, and they otherwise do not drive or use items efficiently. As the engine class increases, however, the AI will start to become more aggressive, drifting along the inside of turns, holding items behind them to block the player's attacks, performing Rocket Starts more often, and generally driving better and becoming more difficult to defeat.
In the games
In Super Mario Kart, getting gold trophies in all four cups in 100cc will result in unlocking the 150cc class.
In Mario Kart 64, this was the first time 150cc wasn't unlockable, and 100cc was simply the middle cc class.
In Mario Kart: Super Circuit, getting gold trophies in the first four cups in 100cc will unlock the Special Cup for 100cc play. Replaying all cups in 100cc and getting at least 100 coins, as well as another gold trophy in each will unlock the respective Extra Tracks for 100cc play.
In Mario Kart: Double Dash!!, getting a gold trophy in the Mushroom Cup in 100cc will unlock the Rattle Buggy. Getting a gold trophy in the Flower Cup in 100cc will unlock the Waluigi Racer. Getting a gold trophy in the Star Cup in 100cc will unlock the Special Cup. Finally, getting a gold trophy in the Special Cup in 100cc will unlock Toad, Toadette, and the Toad Kart.
In Mario Kart DS, getting gold trophies in the entire Nitro Grand Prix in 100cc will unlock a third kart for every character available in the game so far. Getting gold trophies in the entire Retro Grand Prix in 100cc will unlock Waluigi.
In Mario Kart Wii, getting a gold trophy in the Special Cup in 100cc will unlock Outfit A for your Mii. Getting a gold trophy in the Leaf Cup in 100cc will unlock Dry Bones. Getting at least a 1 star ranking in the cups of the Retro Grand Prix in 100cc will unlock Bowser Jr.. 100cc is initially the weakest available engine in the online VS Race, and is reserved specifically for Bikes only.
- The term cc as used in the names of different engine classes stands for cubic centimeters, and refers to the engine displacement of an internal combustion engine (such as the ones used in go-karts and cars). The larger the engine displacement, the more powerful the engine is. The average modern economy car has an engine displacement of about 1400cc to 1800cc.