What is the benefit of coins in Mario Kart 8?
Coins have three benefits, speed, boosts and unlocks.
Speed
Each coin you collect boosts your overall speed. Increasing your top speed, especially on straightaways. You max out at 10 coins.
Boosts
For each coin you collect you get a very, very tiny speed boost -- even after you've collected the maximum of 10 coins.
Unlocks
You must collect coins to unlock karts and parts. Each coin you collect adds to an overall coin count.
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