OP you need a tune adjustment as suggested. Auto with 3.73 gears is in 3rd gear easily up until 100mph. 4th gear (100+ mph) is where the car should "feel" weaker in comparison to the other gears.
I watch my spedometer running down the 1/4 at the end of each pass, because unfortunately, I have a 4th gear shift just before the trap. I finish in 4th gear at 102mph
Grabber Blue 2011 V6 Premium A6 Coupe Mods: MPT 93 Tune, FRPP 3.73 Gears, BBK Longtube Headers w/ O/R Xpipe, Steeda CAI, Dynomax 2.5" Ultra Flo Catback, Boss302 STB, J&M LCA, Whiteline Relocation Brackets, Eibach Sportlines, 18x9/10 '10 GT500 rims 255/45, 285/40/18 Nitto555 Next: BBK 73mm TB, Ported Intake Manifold, DSS Al Driveshaft, . Styling: 15% Tint, Black Spoiler, Decklid Panel, & Grille Surround. Chin Spoiler, Hood Spears
Best to Date - 13.212 @ 105.79 - Uncorrected