A vehicle exhaust system and method of minimizing a leaked mass flow comprising an exhaust component defining a central axis and having an inner surface and an outer surface, such that the inner surface defines a primary exhaust gas flow path extending along the central axis from an inlet to an outlet, and a surface component having a hood spaced from the exhaust component to define a reservoir having a reservoir volume (V), the reservoir comprising a reservoir inlet fluidly coupled to the primary exhaust gas flow path and defining an inlet area (A), and a reservoir outlet fluidly coupled to an outside environment. The reservoir volume and inlet area having a defined relationship. The reservoir volume and a mass flow through the inlet area having a defined relationship.