My understanding is that on a forged engine things like the piston clearance (over time can cause piston slap compromising the rings and cylinder bore) and obviously the overall higher engine power output would be things that reduce engine life span... not to mention the owner / driver of the car which is another factor of the cars future reliability.

That being said if the engine was built / maintained correctly there is no reason why it wouldn't have plenty of life left. Same with a Rotary, they get a bad reputation for being garage queens / workshop whores (which admittedly is where some spend most of their lives).

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MY01 JDM EVO VII - 230KW / 430NM @ 1.6BAR