The MGB GT V8 inlet manifold is a two-piece arrangement specific to the MG application. A Rover penthouse-style cast aluminium base sits in the V between the cylinder heads, with intake ports machined to suit the standard Rover V8 head. A V-shaped MG-specific adaptor bolts to the top of the penthouse base, raising the inlet flange to mount the twin SU HIF6 carburettors at the rear of the engine. This rearward carburettor mounting was MG's solution for fitting the V8 within the standard MGB engine bay without a bonnet bulge, by tucking the carburettors into the available space above the bellhousing.
Manifold Gaskets
Gaskets seal the joint between the inlet manifold and the cylinder heads, between the two manifold pieces, and between the manifold and the carburettors. A complete inlet manifold gasket set provides all the seals needed for a manifold removal and reassembly, and is essential for any work involving manifold removal, re-using old gaskets typically results in vacuum leaks and poor running.
Heatshield
A metal heatshield mounts between the inlet manifold and the engine block, isolating the manifold from radiated heat from the cylinder heads and exhaust manifolds below. The heatshield is V8-specific and is essential for protecting the carburettors from heat soak, without it, fuel can vaporise in the float chambers during hot-running conditions, causing hot-start difficulties and uneven idle.
Carburettor Mounting
The carburettors are mounted on the inlet manifold adaptor with studs, washers and nuts. Sealing washers between the carburettor flange and the manifold prevent vacuum leaks. Studs and fixings are renewed as needed during service work.
MGOC Spares
MGOC Spares supplies inlet manifolds, manifold gasket sets, heatshields, carburettor mounting hardware and all associated components for the MGB GT V8.