{"product_id":"holden-vn-308-304-efi-air-gap-dual-plane-intake-manifold-cast","title":"Holden VN 308 304 EFI Air Gap Dual Plane Intake Manifold Cast","description":"\u003cdiv\u003e\n\u003ch2\u003eHolden VN 308\/304 EFI Air Gap Dual Plane Intake Manifold (Natural Cast Finish)\u003c\/h2\u003e\n\u003cp\u003eUnlock efficient, spreading air-fuel delivery for carburettted Holden V8 powerplants with this Air Gap Dual Plane intake. Specifically engineered for Holden VN and later heads, it’s a robust, natural-cast solution designed to optimize throttle response and mid-range power across a broad RPM band from 1500 to 6500 RPM. This manifold is non-EGR and features a square-bore carburettor pad to accommodate modern aftermarket carburettors with both manual and electric choke options.\u003c\/p\u003e \u003ch3\u003eCompatibility \u0026amp; Fitment\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003eFits Holden 304 V8 engines (will not suit early Holden 308 cylinder heads).\u003c\/li\u003e \u003cli\u003eDesigned for late model Holden VN engine models with EFI; not compatible with VT engines that have factory roller cams.\u003c\/li\u003e \u003cli\u003eIntended for carburettor setups using a square-bore pad; not compatible with factory OEM fuel rails (requires Aeroflow Fuel Rail Kit AF6999-4003).\u003c\/li\u003e \u003cli\u003eFor non-EFI applications, use A6010-4000.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003eAir Gap, dual-plane design to promote even air-fuel distribution and improved throttle response across the RPM range.\u003c\/li\u003e \u003cli\u003eCarburettor mounting pad supports aftermarket square-bore carburettors with both manual and electric choke options.\u003c\/li\u003e \u003cli\u003eNatural cast finish with substantial compatibility for late-head configurations, water necks, air conditioning, and HEI ignition systems in most builds.\u003c\/li\u003e \u003cli\u003eDesigned to maintain steady air-fuel flow for maximum performance and efficiency in carburetted setups.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eTechnical Specifications\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003eRPM range: 1500–6500 RPM (as specified for broad performance across the usable range).\u003c\/li\u003e \u003cli\u003eOverall height from carb pad to bottom: 150 mm (check bonnet clearance).\u003c\/li\u003e \u003cli\u003ePort size: 1.20\" x 2.05\".\u003c\/li\u003e \u003cli\u003eSquare bore carburettor pad; non-EGR design.\u003c\/li\u003e \u003cli\u003eIntake manifold gasket: 5REGIM-308VN.\u003c\/li\u003e \u003cli\u003eCarburettor studs: 5\/16-18\" (x4).\u003c\/li\u003e \u003cli\u003eThrottle bracket mounting hole: 5\/16-18\" (x1).\u003c\/li\u003e \u003cli\u003ePorts: two 3\/8\" NPT ports (with one steel port plug included) and three 1\/2\" NPT ports (with two steel port plugs included).\u003c\/li\u003e \u003cli\u003eFuel rails and plumbing: AF6999-4003 includes 2 x Fuel Rails (-8ORB) and -8AN crossover line with fittings.\u003c\/li\u003e \u003cli\u003eHardware: 6 x mounting brackets, 6 x M6 socket cap screws (25mm UHL), 6 x M6 hex screws (10mm UHL), 4 x M6 nuts.\u003c\/li\u003e \u003cli\u003eFuel system note: This manifold does not work with factory OEM fuel rails; requires Aeroflow Fuel Rail Kit AF6999-4003.\u003c\/li\u003e \u003cli\u003eInjectors: Requires 14mm short injectors (33.60mm length) (sold separately).\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eWhat’s Included\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003e2 x Fuel rails (-8ORB) with Aeroflow connector kit\u003c\/li\u003e \u003cli\u003e-8AN crossover braided line (100 series) with two 90° non-full-flow taper fittings\u003c\/li\u003e \u003cli\u003e3 x -8AN to -8ORB fittings\u003c\/li\u003e \u003cli\u003e1 x -8ORB hex port plug\u003c\/li\u003e \u003cli\u003e6 x mounting brackets\u003c\/li\u003e \u003cli\u003e6 x M6 socket cap screws (25 mm UHL)\u003c\/li\u003e \u003cli\u003e6 x M6 hex screws (10 mm UHL)\u003c\/li\u003e \u003cli\u003e4 x M6 nuts\u003c\/li\u003e \u003cli\u003eIntake manifold gasket (5REGIM-308VN)\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003eInstallation \u0026amp; Tuning Notes\u003c\/h3\u003e\n\u003cul\u003e \u003cli\u003eIntake runners should be port-matched to your cylinder heads for optimal performance.\u003c\/li\u003e \u003cli\u003eEnsure bonnet clearance before installation due to the 150 mm overall height.\u003c\/li\u003e \u003cli\u003eDesigned to work with aftermarket square-bore carburettors; verify choke type (manual or electric) for compatibility.\u003c\/li\u003e \u003cli\u003eNot compatible with VT factory roller camshaft configurations; use appropriate non-EFI or EFI-specific variants as noted.\u003c\/li\u003e \u003cli\u003ePlan for EFI-to-carburettor rail requirements: this intake requires the Aeroflow Rail Kit AF6999-4003 for proper fuel delivery.\u003c\/li\u003e\n\u003c\/ul\u003e \u003ch3\u003ePerformance \u0026amp; Use Cases\u003c\/h3\u003e\n\u003cp\u003eIdeal for carburetted Holden 304 V8 builds aiming for broad, responsive power across idle to mid-range RPM. The Air Gap design helps minimize heat soak, maintains consistent air temperature at the runners, and provides improved throttle response in high-performance street applications and light to moderate race setups. The natural cast finish adds a classic look while withstanding the vibrations and heat of daily use.\u003c\/p\u003e \u003ch3\u003eCompatibility Summary\u003c\/h3\u003e\n\u003cp\u003eBest for: Holden VN-era 304 V8 EFI engines with late-model heads. Not suitable for early 308 cylinder heads or VT-era engines with factory roller cams. For non-EFI engines, choose the A6010-4000 variant. This manifold uses aftermarket fuel rails (AF6999-4003) and 14 mm short injectors (sold separately) for proper fuel delivery.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"My Store","offers":[{"title":"Default Title","offer_id":47273739911338,"sku":"AF6010-4003","price":590.9,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0658\/7829\/4698\/files\/s-l1600_737f23e3-8cf6-4a9c-91b5-d1882bc056d1.webp?v=1753665161","url":"https:\/\/tgmperformance.com.au\/products\/holden-vn-308-304-efi-air-gap-dual-plane-intake-manifold-cast","provider":"TGM Performance Parts","version":"1.0","type":"link"}