Let me explain.
From what emerged from my research, the TVR Typhon/Tuscan T400R/T440R are practically the same car whose name has changed over time. So the blueprint with the measurements (the one I posted previously) is valid for all three denominations. The first thing I did was to measure both models in length. Once I imported the models into blender, I measured them:
360 gtc/modena by RSS--> 4.48 m (0.026 m less than the real Ferrari measurements)
TVR converted from GTR2 without modifications --> 3.90m (50 and more cm less than the blueprint)
TVR upscaled --> 4.42 (0.02 m more than the blueprint)
Let's say that 0.02m are negligible margins of error, 50 and more cm are not.If the GTR2 model was exactly proportioned, the other two dimensions should also be approximately correct. Unfortunately, as you may have noticed, only the width is slightly off (1.85 over mirror against the upscaled 1.87 and 1.77 against 1.90 upscaled*) . The only thing I can think of is that the model isn't perfectly proportioned. The other element that makes me understand that the measurements in the blueprint are actually his is that the wheelbase coincides with the upscaled 3D model (2.574 brought to 2.58 in AC for that 0.02 difference in length). If the length coincides, the wheelbase as well as the height, then I assume that the model had to be upscaled.
As for the wheels, I have to explain myself better this time too. The dimensions were deliberately increased to avoid clipping with the asphalt (beta version) because I had already enlarged them in the Tsunoda version trying to respect the measurements (by doing the upscaling they became larger, now I have already fixed them with the right measurements).
Having read that in GTR2 there are several errors in aerodynamics, physics, etc., I wouldn't want them to have also been made on a graphic/measurement level.
EDIT: let's be clear, I don't want to impose myself. I've just checked and experimented several times and I've come to this conclusion.
*1.90 refers to the width at the rear, the widest part of the car. Tightening it by 0.12 it would no longer have the over mirror measurements, so I assume it has been widened in the racing version or in any case it is not exactly like in reality.