Its not gonna have a turbo straight-six. Toyota only used BMW power plant to minimize cost on the Supra knowing that they aren't going to sell a massive amount of units. The cost to design a new engine is in the billions and if it were to share the same with the Supra they would have done their own design and never let BMW cut into their profits. Which is leads into exactly why its not a BMW straight-six... Toyota will NEVER let BMW take a nickel from one of their best selling models.
