Originally Posted by theDreamer

Why do you think if they could do it they would have?
Technology moves forwards, cost are reduced, and the platform sharing is actually fairly new with recent partnerships in the past decade.

You have to take the current generation with a grain of salt for the future, it is a starting place, but we do not know Nissan's ultimate plant (if even the Z will survive). They could be working on a new engine, platform, components that the 370z could not have had because of initial cost, but now such items like carbon fiber or more aluminum are much cheaper and viable helping keep overall per car cost down but allowing weight reduction.