The cylinder heads on the Rover 3528cc V8 are die-cast in aluminium alloy with iron valve guides and pressed-in valve seat inserts. Each head carries four valves per bank, eight in total, two per cylinder, operated by a rocker shaft assembly running across the top of the head. The combustion chambers are wedge-shaped and finished to give the factory 8.25:1 compression ratio. Both heads are interchangeable left to right on the engine itself but are usually supplied as a matched pair when reconditioned.
Lead-Free Heads
Lead-free cylinder heads are available with hardened valve seat inserts suitable for unleaded petrol use. The original factory cast-iron seat inserts were specified for use with leaded fuel, and although many V8 heads have given long service on unleaded petrol with lead replacement additive, owners planning a sustained-mileage rebuild are advised to specify lead-free heads for full unleaded compatibility. Lead-free heads are supplied on a like-for-like basis with the original seat geometry, so no other engine modification is required.
Valves, Springs and Guides
Inlet and exhaust valves are V8-specific items. Valve springs are conventional single-coil springs with collets and retainers, with full spring sets available. Valve guides press into the head and are renewed during any cylinder head reconditioning. A valve gasket set provides the stem seals, manifold gaskets and other small items required for a head rebuild.
Cylinder Head Bolts
The V8 cylinder head is secured by a set of bolts of three different lengths, the longer bolts passing through the head into the block and the shorter bolts clamping the rocker shaft pedestals at the head edges. The correct number of each length must be used in their original positions to avoid damaging the block. Cylinder head bolts are not normally re-used after a head removal, fresh bolts are recommended for any rebuild.
Head Gaskets
Cylinder head gaskets are V8-specific composite gaskets, with full top-end gasket sets available that include the head gaskets, manifold gaskets, rocker cover gaskets and ancillary seals. The gasket set is sized to suit the standard 88.9mm bore and is the appropriate choice for any rebuild on a standard or near-standard engine.
MGOC Spares
MGOC Spares supplies cylinder heads in standard and lead-free specifications, valves, valve springs, valve guides, valve seat inserts, cylinder head bolts and complete top-end gasket sets for the MGB GT V8, see individual sub-sections for details.