Maruha +1mm Big Valve Set of 16 for Mazda MX-5 NA NB 1.8
Maruha’s +1mm oversize valve set for Mazda MX-5 NA NB 1.8 are an essential part of any high performance naturally aspirated head. The increased size of the valve allows more flow at higher RPMs, which is important to make the most of large cams and high RPMs. The +1mm valves are sized accordingly to use the standard valve seat, however, the valves and seats require machining to guarantee they seal properly together.
Through Maruha’s extensive testing, they have chosen to not use back-cut valve stems to ensure the stem is strong enough to withstand the forces generated at high RPMs. It is recommended that the valve guides are replaced at the same time as the valves to prevent excessive oil consumption and reduce noise in the valvetrain.
Sold as a set of 16 = 8 x Intake and 8 x Exhaust
Suits NA8/NB 1.8L 1994-2004