Whoopsy:
So they souped the GTR to around 700hp then.
Whatever it takes . It's called " run what ya brung " .
Nothing new here and each of these official times posted by a manufacturer surely includes " optimizing " every parameter of alignment ,engine ECU, traction mgmt ,etc -but staying ( you hope ) barely within production tolerance ranges - for that course vs what is normalized assembly line production of what they give you, Joe Customer , off the delivery truck at your dealership.
So since they all do it, the comparo times still have merit.