South Australian company Willall is developing the world’s ultimate Subaru WRX STI and, best of all, you can buy one.

Dubbed the ‘25BB’, it’s conceived as a modern-day successor to the iconic WRX STI 22B and uses Willall’s extensive machining knowledge, proven at drag strips and racetracks around the world, in a coachbuilt widebody shell.

Willall Subaru WRX STI 25BB profile

“We got involved in the high end of racing them with Willall designing a billet crankcase so people can run 800-1000hp without having recurring problems.”

Willall Racing WREJBB

“So we thought ‘let’s make our own widebody for it!’. You can’t get anything wide for these cars other than the front fenders, so we thought we’d metal finish an entire car. It’s WRC blue so we’re going to make it faithful to the whole 22B concept.”

Willall Subaru WRX STI 25BB rear guard

Under the bonnet is a WREJBB capable of 800kW, with Donnon explaining “We have a magic set of cylinder heads and camshafts to make that sort of power, we have a special rotating assembly, which is pistons, crank and rods that take it out of 2.63 litres [and] a specially-made turbocharger system.”

Willall Subaru WRX STI 25BB front

Though Willall’s development car runs a PPG sequential gearbox, Donnon maintains the standard H-pattern manual is deemed strong enough for the road: “The six-speed’s a beautiful thing – it’s a very, very strong gearbox.”

Prior to the widebody mods that are currently being applied, Willall’s development car ran a 9.8sec quarter mile at the Snowy Mountains 1000 (see video below) while its sister car ran a 10.1sec quarter at 233km/h at Adelaide International Raceway. Donnon estimates the 25BB will be good for 0-100km/h in around 2.7sec and 0-200km/h in 6.2sec.

Currently, Willall is building a handful of cars for export, however Donnon says, “we would entertain building one for a local client.” Cost is to be confirmed and would depend on the exact specification of the car, however according to Donnon: “We’re talking GT-R money.”

With the bodywork currently being finalized, the finished 25BB will appear at the Subinats at Phillip Island on July 2, after which MOTOR is promised its own turn at the wheel. Stay tuned for images of the finished car and a full review.

Willall Subaru WRX STI front guard
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