Triumph Spitfire Cylinder Block and Components
CYLINDER BLOCK IDENTIFICATION::
Recessed or Non-Recessed Cylinder Bores
EARLY MkIV engines (to engine number FH25000E) have (as all previous Spitfires) Non-Recessed cylinder bores, and use a plain head gasket.
LATE MkIV engines (from engine number FH25001E) and ALL 1500 engines have a Recessed Lip at the top of the cylinder bores adjacent to the block face, necessitating a particular type of head gasket, which can be identified by a small ‘Tag’ that stands proud at the rear of the block.
CAMSHAFT BEARINGS & CYLINDER BLOCKS:
Original Block Specification
Mk1 camshafts ran directly in the cylinder block, as did early Mk2’s up to engine number FC60122.
Cylinder blocks for Mk2’s from FC61023, all Mk3’s and early MkIV’s (to FH 25000E), had enlarged drillings in the cylinder block to accept replaceable camshaft bearings (part number 142647K) though the camshaft journals remained the same diameter.
Late MkIV (from FH25001E) and all 1500’s had revised cylinder blocks allowing the camshaft to run directly in the block without the use of bearings.
Mk1 & Mk2 (to FC61022) used small diameter tappets/cam followers and from FC61023 onwards large diameter tappets/cam followers.