You're right! The CA18DET was the engine for the 180SX, which was the S13 hatchback with the pop up headlights. This is why the SilEighty is called the Sil(silvia)Eighty(180SX).
I'm not sure about really high power outputs, but I'm sure 400hp can be achieved with the CA18... Sorry, I'm in North America, and we stopped getting the CA18 after the S12 200SX(didn't we?
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