the volvo diagram doesn't show me anything new as far as design characteristics. What I would like you to do now is to measure the clearance between the engine and firewall, then the dimensions of the tunnel, and I think the light-bulb will come on as to why this would be more difficult than you can imagine. not only clearance as it exists when stationary, but also think about the amount of torque-over the drive train gets during hard acceleration. I think you'll find this is the reason it hasn't been done yet.
Nobody's going to knock you for presenting an idea. That's what this forum is about. However, turbo placement is something we've considered very in depth, and there's very few places that one can be mounted for practical daily driving.
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