[Auto_Fpv]

Hoping for some clarification>Running stage 2 Bootmod3 and removed max limiter in options.. went out for a top speed run and trans was in S6th gear (sportauto wasnt using paddles) wile aproaching 160mph car hit 160 shift into S7th but instantly rpms start bouncing like It hit limiter and tranny would shift back and forth from 6th and 7th I was running out of road so didnt have time to manual shift paddles. so Im thinking its one of two things limiter wasnt removed via flash or there is a limitation to auto trans ..Any insight would be greatly appriciated.

[Mason Hatcher]

Holy shit! Where can you run 160?

[Auto_Fpv]

Originally Posted by Mason Hatcher

Holy shit! Where can you run 160?

for legal purposes lets just say it was an abandoned airfield

[230iZTR]

I've never done such a thing myself, but I'd assume it's because gears 7 (.839:1) and 8 (.667:1) are functionally overdrive gears for cruising. You're getting more power to push faster in 6th (1:1) but running out of rpms, while in 7th you've got plenty of rpms left but the ratio is reducing your mechanical advantage for acceleration so you wind up losing speed against the ridiculously large drag you'd be experiencing (drag goes up exponentially with velocity). The ECU sees you're decelerating despite the gas being fully depressed, so it tries to switch you back to 6th for better acceleration to fight drag.

Basically, it appears BMW did a pretty good job of matching the car's electronic limiter to it's drivetrain and aerodynamics. Even with the speed limiter removed, you can't go faster in practice without significantly more power and torque or aero changes to offset the exponential increases in drag, so it doesn't matter much.