Performance Parts can be equipped to alter a vehicle's engine, forced induction, transmission, suspension, brakes and tyres with each capable of altering the characteristics of a vehicle as well as improving its overall statistic performance.
The characteristic altering aspects of a performance part is portrayed by the colour of the icon for the part:
Beige - Unbiased
Blue - Bias towards acceleration
Red - Bias towards handling
Green - Bias towards top speed
Performance parts are divided into four main Stages; Street, Race, Pro, and Ultra with each providing an increased margin of performance capabilities. Each stage is displayed by a star rating system and a background pattern with more stars alongside a different pattern representing a different stage;
Street - Minute alteration in vehicle performance.
Race - Marginal alteration in vehicle performance.
Pro - Significant alteration in vehicle performance.
Ultra - Excessive alteration in vehicle performance.
Elite - Intensive alteration in vehicle performance.
The performance alterations of a part within a given stage can also differ depending on the Rarity of the part. Rarer parts offer an increase in performance compared to its common counterpart towards an aspect based on its colour. Rarity is divided into Improved, Sport or Tuned with each being represented by a different font colour;
Improved - Standard performance part
Sport - Slightly altered performance part
Tuned - Moderately altered performance part
Custom parts are only found on certain Best in Class style cars and can not be obtained through any other means. Additional Custom rated parts were created but were never released.
Custom - Bespoke altered performance part
Ultimate rarity parts are a series of unreleased performance parts, and offer the highest performance rating for a part's stage.
Ultimate - Excessively altered performance part
There are several fictional manufacturers that produce different stages of performance parts, with each offering a vehicle altering series of characteristics and part rarities.
There are five Street Stage performance part manufacturers with four of them offering their parts of all rarities for a Cash price. They can be found within the Performance Shop section of the Safehouse.
There are four Race Stage performance part manufacturers with one of them offering parts equipped to some vehicles purchased with SpeedBoost. They can be obtained from either the Lucky Draw at the end of each event or by purchasing Silver, Gold or Platinum Performance Card Packs.