Use this plug and play low frequency MAC solenoid if retrofitting a single turbo kit that runs an external wastegate. Includes plug and play harness connector for no splicing! The 3 Port solenoid controls boost up to 2.5x spring pressure while the 4 Port solenoid controls boost up to 6x spring pressure. With the 4 Port you can run a lighter wastegate spring, for example, 6psi, and provide a much wider range of control which is often useful for improved traction in lower gears.

See images for plumbing instructions.