1.4L 16v - B14NEH 

The B14NEH is the late version of the Vauxhall/Opel 1.4 16-valve turbo, taken straight from the A14NEL. One item is listed here, and that is by design: Wossner forged pistons. On this block the question is not stroke but detonation margin: raise the boost pressure, advance the ignition, and the standard piston crown works beyond what its casting allows. A forged piston brings a thicker crown and better hot strength, provided the cold clearance quoted by the maker is respected.