Cause the 3RS will make more downforce than the Cup car in certain situations, so it will pull more Gs. 

Off the top of my head, first corner I can think of would be Pouhon. Yeah sorry Spa is my absolute favourite track and I always replay it in my head. In a Cup car I had to brake to get into it in a 997 Cup car. Hamilton did it flat a few times in Quali trim with softs and super softs. Another corner that comes second would be the 2nd kink at Blanchimont, I had to tap the brakes a bit/major lift to get the turn in in a Cup car. 

Cup car was aero limited in those 2 turns for sure. Radillon isn't that big a deal, After braking for Eau Rouge, I am pretty much flat out of it though Radillon in a Cup car. All other corners at Spa is mechanical grip limited. And the burst of straights in between corners there a Cup car will have the advantage being a lighter car. 

13 and 14, Piff Puff, is my least favourite corners in Spa, I simply can't do the deep trail through 13 the fast guys can do, they literally trail brake the whole way through 13 to set up the entry into Puff, aka turn 14. If I try that myself I would spin out at 13. I watched plenty of footage of the Carrera Cup guys running there, I just cannot replicate how they do it. 


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