The CV-150B is a valve guide assembly designed to lock in place and provide tight tracking and accurate alignment of the valve stems and valve guides. The CV-150B is a self-contained unit, consisting of four stainless steel guide collars, two upper and two lower steel guide bodies, and two upper and two lower stainless steel valve stems with O-rings. This provides an improved seal and strength to the valve stem and guide body, which reduces vibration and extends valve stem life. The valve guides are rotatable and adjustable to account for wear and tear or different engine configurations. It uses a low-torque stainless steel fastener to secure all components.