I love all the talk of what it will be called... WHO CARES haha, I shaved my 370z badge off and when people ask I tell them its a Z...
The motor already exists so HP perspective is pretty easy to guesstimate. Its a 400hp TT motor... If we go off from previous G/Z platforms the Z will typically have the same or slightly more power and weigh less than a G/Q.
I guessed Nissan would be releasing a TT V6 a VERYYYY long time ago.
THat being said my guess (which has been good so far) is
Base Z 2.0T 300ish hp
Sport Z 3.0TT V6 400-410hp
Nismo 3.0TT V6 465hp
Look back at this once its released
Also if you look back to my posts years ago I was almost exactly the same before we even knew about these Engines... Maybe I am good at guessing OR.... Top Secret haha