FD3S Water Neck
A simple way to eliminate the AST tank and make the engine bay cleaner. Our custom water neck replaces both the boxy OEM water neck and the OEM or aftermarket AST tank. We combined both into one to help clean up space as well as reduce future coolant leaks by deleting the hoses going to the AST tank. We offer the water neck with or without the coolant level sensor. Polishing available at extra cost.