I have a more practical reason for you to not drop a V8 in there: you're getting a car with questionable structural integrity (rust, etc) and don't plan on doing any chassis reinforcing. That's a recipe for a twisted chassis when you throw in the torque from a V8, or even a turbo swap. Also, in many cases an American V8 swap into a relatively rare "JDM" vehicle will decrease the resell value should you decide to ever sell it.