Lol so we're gonna go down this debate to..
Do OEM manufacturers make 1100 twins, with high compression, stroker cranks etc.. that take extensive amounts of abuse? of course they can design the smaller motors with a cast piston as they wont take as much.
The forged piston will hold up to all of that a hell of a lot better without breaking into pieces. In the end i dont know of one big engine maker who doesnt use Wisceo forged because of this. You can control the expansion rate of a forged piston more than a cast as well. When you are having tuning issues your forged ones wont break or melt into small pieces due to the increased density of the forged..
Looked all this stuff up for you beyond what i said...
Forged pistons are mechanically shaped into a piston shape. They are hammered, pressed (forged) into a mold forming the piston in turn removing any possible porosity and also pushes the alloy grains together tighter than can be achieved by simple casting alone. The result is a much stronger material.
By utilizing state-of-the-art CNC machines, most manufacturers can maintain exact specifications and tolerances. This makes them structurally more durable. Forged pistons are well known in the racing and performance industry because of their ability to withstand more heat, higher RPMs, higher boost and higher temperatures. But forged pistons are not just for professional racers. Another advantage to a forged piston is that they can be individually made to any custom size or specification without the high cost of casting.
A cast shaped component means that the material has been melted and then poured into a mold that basically shapes the piston. The advantages are many, for example: a possibility to add other components like silicone, carbon, zinc and so on in order to gain certain properties. The aluminum itself doesn't build up inner tension as much. It is cheap. The density of the material doesn't increase which means it could be kept light.
There are disadvantages also, of course. The piston will be weaker in structure. It is often heavier since the manufacturer has to increase wall thickness in order to achieve sufficient strength. The heat expansion cannot be controlled and is therefore often not completely round since the piston pin requires some material on the inside. They are also produced in bulk with most manufacturers only producing sizes that are close to factory specifications. This also makes them more affordable.
