[MVF4Rrider]

Originally Posted by swamp2

I disagree. Again it depends on which definition of faster you use, in a single gear, yes, always; across muliple gears, maybe yes, maybe not, depends on the specific car. Please have a look at the lengthy debate on this topic elsewhere on the forum. In addition don't forget that even now both the 6MT and M-DCT are pretty traction limited in 1st gear.

Well, you’re entitled to disagree but in this case you’re taking into consideration things outside of the real world, which is outside the context of this discussion. BTW, I meant to say quicker, not faster. Back on point: rear diff gear changes (shorter gearing) affect every gear at every rpm by the same exact % increase in multiplied torque to the pavement. Therefore it will make the car “quicker” in any gear and at any rpm when simply opening the throttle to increase the rate of acceleration and speed. It also enables the engine to reach terminal speed quicker in each gear, which is an advantage. Now, when including constraints such as closed circuits, 0-60 times, ¼ mile times, etc. the gearing change could have adverse affects IF and only IF an additional gear change is required. But I don’t live in a world where that matters so I’ll take the constant % increase of multiplied torque and enjoy the quicker acceleration under every conceivable real world condition. Again, stepping up 1 gear ratio is not going to lend itself to adverse affects comparatively. Going too short on the final drive could. I don’t advocate radical gear changes. IMO, BMW should have chosen the 3.91 rear diff ratio as opposed to the 3.62 in my cars. I’m sure they did this for fuel economy sake, and to perhaps limit stress on the driveline. 3.91 is the perfect gear to increase torque (and therefore acceleration) without adversely affecting traction. It would at least be nice if ordering a “performance package” option that it included things like a bump in final drive, perhaps a more aggressive fuel map, and no speed limiter…instead of more heavily bolstered seats and other typical non-performance additions.