There are only two reasons the M6 would be faster in a straight line. First would be it is 45 kg lighter. Second is it may have stickier tires. Neither of these reasons would contribute a significant amount. Look at it this way, if you're cruising along in your M5 with a quarter tank of gas, and come up on an M6,with a full tank of gas, you'll be dead even.Dubai M5 said:The M6 does o-100 in 9 sec as shown in autocar magazine.
M5 does it in 9.2 as shown in sport auto and 9.8 as shown in autocar. :confused2
If sport auto times are correct then the M5 performance is so close to M6.