The EVP V-FLOW reinforced airbox intake hose is required for all big injector tunes and recommended for all EVP tuning stages. The OEM hose is made from soft, unreinforced rubber which implodes when the airflow demands are slightly higher than stock. (A video demonstrating this can be seen on our website under this product page). The EVP V-FLOW reinforced airbox intake hose is made from high strength silicone with internal steel wire reinforcement which guarantees the hose cannot implode.
Other EVP reinforced silicone products to replace the inferior OEM parts are also part of a complete kit and are available separately.