PORTS AND FITTINGS The fuel rail ports are tapped for 8AN ORB. 8AN ORB Adapter Fittings 8AN ORB Direct Mount Regulators 8AN ORB Fuel Pulse Dampers Fuel Pressure Gauge Adapters Appropriate fittings must be selected based on the specific application. Ample space around the fuel rail port(s) is necessary for larger accessories such as fuel pressure regulators, fuel pressure gauges, and fuel pulse dampers. To verify clearance, the dimensional drawings on the product pages can be used as a reference guide. COMPATIBILITY 02-09 VW Golf R32 01-03 VW Beetle R Si 06-08 VW Eos 02-08 VW Phaeton 05-10 VW Touareg 03-09 Audi A3 01-10 Audi TT 04-07 Porsche Cayenne FUEL RAIL Manufactured with A 0.7" large internal bore, the Radium Engineering fuel rail can support all necessary engine power requirements. there is just enough clearance with the OEM intake manifold when using OEM height fuel injectors. Insulating mounting spacers are provided to prevent thermal heat transfer into the fuel. INJECTORS Like the OEM fuel rails, the injector bores are 14mm ID so factory injectors (or any equivalent aftermarket injector) can be used.  the factory injector retaining clips can be reused. FEATURES Lightweight aluminum construction Inner bore diameter: 0.7 inch Anodized surface finish for wear and corrosion resistance No special tools required for installation Thermal insulating spacers  INCLUDES 1x 3.2L 24V VR6 Fuel Rail 4x Thermal Insulating Spacers 4x Rubber Spacer Retainers 4x Stainless Screws, M6x 1mm Instruction PDF