Austin Motor Company's small straight-4 automobile engine, the A-Series, is one of the most common in the world. Launched in 1951 with the Austin A30, production lasted until 2000 in the Mini. It used a cast-iron block and cylinder head, and a steel crankshaft with 3 main bearings. The camshaft ran in the cylinder block, driven by a single-row chain for most applications, and with tappets sliding in the block, accessible through pressed steel side covers for most applications, and with overhead valves operated through rockers. The cylinder head for the overhead-valve version of the A-Series engine was designed by Harry Weslake – a cylinder head specialist famed for his involvement in SS (Jaguar) engines and several F1 title winning engines. Although a 'clean sheet' design the A-Series owed