i'm not too surprised they are fairly evenly matched. Having followed a good number of gen2 gt3s this year, they are by and large not getting any kind of gap down long straights at Silverstone given roughly equal entry speeds. The 4.0 has a slightly gearing (with smaller wheels) advantage and a touch more mid range but the new car does rev that extra 500rpm. net result it seems in my experience anyway there's very little between them.

At the end of the day, 500PS NA engine car is very close to another 500PS one with similar gearing and engine capacity....not exactly a shocker they are fairly even?