For years, automotive purists have leveled one major critique against the modern Toyota GR Supra: it has a BMW engine. While the B58 turbocharged inline-six is an undeniable masterpiece of engineering, Toyota faithful have never quite stopped dreaming of a flagship Supra powered by a true, in-house Toyota powerplant.Well, Toyota has finally answered those prayers by building a GR Supra with a massive, naturally aspirated Toyota V8. It sounds incredible, it looks aggressive, and it fixes every purist complaint in the book.There's just one tiny problem: you aren't allowed to buy it.The 2026 Repco Supercars ChallengerInstead of hitting showroom floors, this V8-powered beast is bound exclusively for the racetrack. In a massive shakeup for Australian motorsport, Toyota has officially announced it will enter the Repco Supercars Championship starting in 2026.AdvertisementAdvertisementThe Japanese automaker is building a fleet of Gen3 GR Supras to take the fight directly to the Ford Mustang and Chevrolet Camaro. Under the Gen3 regulations, these race cars require a thumping V8 engine to maintain parity—which meant the road-going Supra's inline-six simply wasn't going to cut it.To solve this, Toyota Australia's design and engineering teams reached into the brand's parts bin and pulled out a legend. The Supercars GRIf that engine code sounds familiar, it should. The 2UR-GSE is Toyota's venerable all-aluminum, quad-cam V8. It is the exact same naturally aspirated workhorse that gives cars like the Lexus RC F, GS F, and LC 500 their glorious, roaring soundtracks, and it famously powered the 2019 Dakar-winning Toyota HiLux.By shoehorning a modified 5.2-liter version of this V8 into the chassis of a GR Supra, Toyota has essentially created a modern-day muscle car.AdvertisementAdvertisementTo ensure the new racer is competitive right out of the box, Toyota is partnering with Walkinshaw Andretti United (WAU) as its homologation team. Supercars veterans Chaz Mostert and Ryan Wood will pilot two of the Supras. Brad Jones Racing (BJR) will also step up to field a four-car fleet, bringing the total to six V8 Supras on the grid for the debut season.The Forbidden FruitFor racing fans, the arrival of a third manufacturer to the Supercars grid is the best news the sport has had since 2019. But for street-car enthusiasts, it is a bittersweet reveal.The digital renders and the clay models displayed by Toyota showcase a GR Supra widened, lowered, and perfectly proportioned around that V8 powertrain. It is the exact aggressive, unapologetic flagship sports car that Toyota fans have been begging for since the MkV Supra debuted.Unfortunately, Toyota has explicitly stated this is a purpose-built Supercar to comply with racing regulations. The road-going GR Supra will continue to rely on its BMW-sourced powertrains, meaning the V8 Supra will remain the ultimate forbidden fruit.AdvertisementAdvertisementSo, when the 2026 Repco Supercars Championship kicks off, you can definitely cheer for the roaring V8 Supra on your television screen—just don't expect to ever see one parked in your local Toyota dealership.