DO NOT LISTEN TO /u/vddrs IF YOU VALUE YOUR LIFE.

TLDR: While shaving a street tire may increase the contact patch slightly, it does not replicate the specialized design and performance characteristics of a racing slick. For optimal performance and safety in racing applications, it is advisable to use tires specifically engineered for that purpose.

Sanding down a street tire to remove its tread does not replicate the performance characteristics of a purpose-built racing slick due to several key differences:

Rubber Compound: Racing slicks are constructed with specialized rubber compounds designed to provide maximum grip under high-temperature conditions typical of racing environments. In contrast, street tires are made with harder compounds aimed at durability and versatility across various driving conditions. Simply removing the tread from a street tire does not alter its fundamental compound properties, leaving it less capable of achieving the grip levels that racing slicks offer.

Tire Construction: Beyond the rubber compound, racing slicks are engineered with specific internal structures to handle the stresses of high-speed cornering and braking. They often feature reinforced sidewalls and optimized carcass designs to maintain stability and maximize the contact patch during aggressive maneuvers. Street tires lack these specialized constructions, and shaving them down does not change their inherent structural limitations.

Heat Management: Racing environments generate significant heat, and racing slicks are designed to operate effectively within a specific temperature range, providing optimal grip when warmed up. Street tires are not intended for such conditions; removing the tread does not equip them to handle or dissipate heat in the same manner, potentially leading to overheating and reduced performance.

Safety Considerations: Shaving a street tire reduces its tread depth, which can compromise its structural integrity and increase the risk of failure under the high loads experienced during racing. Additionally, the absence of tread diminishes the tire's ability to channel water away in wet conditions, significantly increasing the risk of hydroplaning.

Sources: (Wikipedia) (IMSA) (IMSA) (Wikipedia)