Jenvey Honda 94x51mm Machined 50DP Carbon Airbox BackplateJenvey Dynamics 50 mm Deep Carbon Fibre Airbox Back Plate Machined with 94mm Centres x 51mm Bore for Honda S2000 or K20 Engines. This Airbox Backplate creates more room for Fuel Rail and Throttle Linkages. This also can use a slimmer Air Filter. With this Airbox using 90 mm Air Horns we use a 90 mm Deep Filter which in most applications is much easier removed and fitted when in place. Specifications Engine Honda S2000 or K20 Bore Diameter 51 mm