GENUINE OEM HONDA CYLINDER HEAD ASSEMBLY FITS GX340 GX390 / ASSEMBLED. Honda Cylinder head that is completely assembled. Valves have been lapped in already. Just need to mount the cylinder head to your engine. Comes with head gasket. Fits GX40, and GX390 engines. Our Dealerships : Kohler, Toro, Briggs & Stratton, Honda, Exmark, Echo, Walker, and more! Listing and template services provided by inkFrog.