Cylinder Block Characteristics (BMW 3 Series E21)

The cylinder block is cast from a special grey cast iron and is integral with the cylinders.

Cylinder diameters

Permissible ovality of cylinder mirrors, mm: 0.01–0.02.

Permissible taper of cylinder mirrors, mm: 0.01.

Permissible non-perpendicularity of the cylinder axis to the main bearing axis: 0°5'.

Total clearance between piston and cylinder (when worn out), mm, no more than: 0.010-0.15.