There are two aluminium cylinder heads with 4 valves per cylinder on top. (mywikimotors.com)
New aluminium cylinder block with offset crankshaft was developed for the engine, Piston stroke is 90.1 mm, and cylinder diameter in this engine is 84 mm. (mywikimotors.com)
[5] Engine output went up from 40 to 43 PS CUNA (32 kW)(48 PS SAE) at 4,800 rpm, thanks to a larger carburettor, a new aluminium cylinder head, [5] and a water - cooled inlet manifold with an individual duct per each cylinder. (en.wikipedia.org)