The cylinder heads are unique to each cylinder
bank. Deep seated bolts, to reduce distortion,
secure the cylinder heads to the cylinder block.
Two hollow dowels align each cylinder head with
the cylinder block.
The cylinder head gaskets consist of a silicon
beaded composite gasket with metal eyelets for
the cylinder bores, similar to that on the AJ16
Each cylinder head incorporates dual overhead
camshafts operating four valves per cylinder via
solid aluminum alloy valve lifters. Steel shims in
the top of the valve lifters enable adjustment of
The lightweight valve gear provides good
economy and noise levels. Valve head diameters
are 31mm (1.220 in) for the exhaust and 35mm
(1.378 in) for the intake. All valves have 5mm
(0.197 in) diameter stems supported in sintered
metal seats and guide inserts. Collets, valve
collars and spring seats locate single valve
springs on both intake and exhaust valves. Valve
stem seals are integrated into the spring seats.
The camshafts are manufactured in chilled cast
iron. Five aluminum alloy caps retain each
camshaft. Location numbers, 0 to 4 for the intake
camshaft and 5 to 9 for the exhaust camshaft,
are marked on the outer faces of the caps. The
rear of B bank intake camshaft has a timing ring
for the camshaft position sensor. A flat,
machined near the front of each camshaft,
enables the camshafts to be locked during the
valve timing procedure.
CAMSHAFT POSITION SENSOR
The 14 mm spark plugs, one per cylinder, locate
in recesses down the center-line of each cylinder
An engine lifting eye is cast into the front of each
cylinder head (the rear lifting eyes, one on each
cylinder head, are bolt-on tools).
TIMING DISC STARTER DRIVE PLATE