It's Real! Subaru BRZ STI Prototype Caught Testing

Bigfoot, Nessie, the Subaru BRZ STI. Finally there is undeniable proof that one of them exists... or at least a prototype of which. Our spy photographers recently caught up with a BRZ STI mule testing in the wilds of Ann Arbor, Michigan showing off its dramatic new styling cues.

After two years of teasing and promising, it seems the BRZ STI may be destined for production after all if these spy photos are any indication. Or at least an STI-tuned performance spec. The prototype seen here shows off a massive new wing, sharp new wheels, and an aggressive body kit. The front of the car is covered in camouflage, likely hiding a more distinctive grille. The rear, though, doesn't receive any new design cues (at least not yet).

Based on previous reports, performance isn't expected to increase dramatically over the base model. The engine will most likely get a slight bump in horsepower – as much as 230 horsepower (171 kilowatts)– but most of the modifications will be seen in the suspension, brakes, and aerodynamics.

No word on when Subaru will release the BRZ STI in full, if at all. The company said back in 2015 that it would be a "couple years" before we saw the new performance model in the flesh, teasing us with the BRZ STI concept in the meantime.

For now buyers will have to make do with the standard BRZ, which pumps out 205 hp (152 kW) courtesy of a 2.0-liter engine. The base BRZ will set you back $25,495, while the more expensive Limited model will cost you $27,645. Expect the STI to cost closer to $35,000 if and when it does go into production.