The engine compartment on a Tundra has got just a bit more room than that of oh, I don't know, ANY turbocharged car and yet they still manage to make those work just fine. I don't think there'd be any significant heat issues with an underhood turbo (or two
) on the Tundra.
I'd rather have a supercharger though, this is a truck afterall, I need low-end torque.