I hear what you are saying, but Porsche are really good at making cars that are greater than the sum of their parts, especially road cars driven on tracks. Effective downforce, weight distribution contributing to traction, braking - their stuff is good, no doubt helped by the huge amount of track testing that is done in their cars by factory racing drivers. Another big advantage that they have is that their entire 'GT' range has been undergoing incremental improvement for two decades now, continually honing and refining cars that were great to begin with.I really have no idea if it will or not..:but assuming equal tires...the GMA is roughly 1000lbs lighter with 150hp more. That’s a pretty big advantage. It would be pretty surprising if it didn’t keep up with a GT3 on track.
Although not in its 'GT' series, who would have imagined that the 918, with its power and weight disadvantages, would be faster around the 'Ring than the P1 was? And yet indeed it was faster.
The T.50 and T.33 are intended to be driver's cars, not track-day specials. I have no idea how fast around a track they will be relative to a GT3, but I would not bet against the latter.