Anyone have an idea what type of pistons these are? I purchased these years ago from eBay and where advertised as an accralite forged pistons. Diameter is 81.5mm (1658cc) However I've never found accralites with that type of Crown. You can tell my the first and forth piston the centre has a higher ring than the rest of the piston.

The car is running omex management and 28psi,
Are these pistons up to it or am I gonna need an engine soon?