Previewed about a month ago, Subaru’s swan song for the EJ20 engine has made its first public appearance today on the dawn of the Tokyo Motor Show where it shares the spotlight with the new 2020 Levorg prototype. The flat-four mill made its debut back in 1989 on the JDM-spec Legacy and has since powered a variety of Subie models with or without forced induction.

The last hurrah for the horizontally opposed EJ20 is represented by a special-edition WRX STI based on the Japanese-market Type S model. The turbocharged 2.0-litre unit pumps out 304 bhp and 311 pound-feet of torque channelled to both axles through a six-speed manual gearbox as the car gods would’ve wanted.

Gallery: Subaru WRX STI EJ20 Final Edition Prototype

From the glorious 19-inch BBS gold wheels backed by Brembo brakes to the STI bits inside and out, there’s a lot to like about the EJ20 Final Edition. Well, maybe except for the fact it will remain a Japan-only affair. There are more changes than meets the eye as Subaru has also tweaked the engine, clutch, and flywheel, along with adding a generous amount of safety equipment.

Subaru will make only 555 examples of the EJ20 Final Edition at a starting price of ¥4,110,000 (approx. £29,500 at the current exchange rate). It will stop taking orders from customers for the WRX STI speedy saloon in Japan on December 23 as a result of retiring the engine.

It is believed the next-generation WRX will be unveiled before the end of 2020 and it’ll quite possibly have a smaller engine. The aforementioned Levorg estate is due to go on sale next year with a newly developed 1.8-litre turbocharged engine, which may or may not find its way underneath the WRX’s bonnet.