Originally Posted by AndreyATC
I dont think 550i is going to be faster than S6 even with such upgrade
In fact, i'd be surprized if it even catches S6
I just bought one and this thing is a beast
It is great deal faster than current 550i in any speed range
I've had pretty extended test drive in 550i, before i bought my S6, so i can compare
Seems hard to believe it wouldn't be. 550i Xdrive will have 445 hp & 480 lb/ft tq vs. the S6's 420/406. BMW is 120 lbs heavier. Audi lists S6 0-60 at 4.5 and BMW lists pre LCI 550i Xdrive at 4.7. I think an additional 45 HP and 30 lb./ft torque, will make the 550 a 4.2 0-60.