How long do JDM engines typically last?

With proper maintenance: Toyota 2JZ-GTE/2JZ-GE: 300,000+ km. Honda B-series/K-series: 250,000+ km. Nissan RB/SR: 250,000+ km. Mitsubishi 4G63T: 200,000+ km. Mazda 13B rotary: 80,000-120,000 km (rebuild interval, not failure). Turbocharged engines generally have shorter lifespans than naturally-aspirated ones.