Performance parts are available as one of six part types and improve different performance aspects of a vehicle:
- Top Speed - Engine, Turbo
- Acceleration - Gearbox, Wheels
- Nitro - ECU, Nitro
The effectiveness of a part is determined by its rarity rating, with rarer parts giving higher performance increases than parts that are less so. The rarity classes are:
Each performance part is categorised in a car class - players are unable to install performance parts for a different class.
All performance parts are made up of different recipes of materials. Installing a material item will instantly increase a vehicle's PR. After completing a part type's recipe, players are able to rebuild it to further improve their PR. Rebuilds can be repeated for a limited number of times that are indicated by the number of stars, although the star rating of a part must not exceed that of the player's car. Exhausting all rebuild options requires the player to install a part with a better rarity rating.
Materials are rewarded to players for completing race events and can be randomly found in crates from the Loading Docks store. Players are also able to highlight any missing material's event.
Conversion Kits can be used to upgrade a part type's rarity. They are available for all part types and rarities with the exception of Legendary. Players are rewarded with Conversion Kits of any rarity for completing Tuner Trial events, although each day is featured with a certain reward:
A higher car stage is required for players to install performance parts with higher rarity ratings. Car stages are unlocked after collecting a certain number of blueprints.