A valve assembly for a central tire inflation system is provided. The valve assembly includes a first housing having a first port connected to a second port via a cavity. The second port is in fluid communication with a wheel assembly. A biasing member is disposed in the cavity adjacent a first perforation formed in the first housing. A valve member is contacted by the biasing member. The valve member includes a first portion having an outer surface which is unbroken adjacent an end to allow a pressurized fluid to flow around it. The first portion reduces in diameter toward the end.