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(To the more pragmatic and patient posters, yes I know that no hard data exists and that we don't really know what final gear ratios for the M Coupe are and that it makes sense to wait to see the real numbers before commenting. I can't argue with that, so I won't. But I'll post anyway.)
My primary assumption is that the gearing for the M Coupe will be the same as last year and that the BMW's stated 2000 0-60 times of 5.1 and 2001 times of 5 are reasonably accurate.
Assuming this, the main benefits of the S54 engine in regard to better breathing at the increased redline are left on the table. The primary reason that we may not see a dramatic reduction in sub 70mph acceleration is not due to a lack of increase in torque but to the fact that the gear ratios have not been changed.
The real benefit of a high redline with a good torque spread is the ability to increase the gear ratio and thereby increasing the torque at the rear wheels. (This is why hp is an important measurement of capacity for work)
Example: 2 Cars with 200ft/lbs at all rpm(hypothetical) one with a 4k redline and one with 8k redline. The first car can reach 40mph with a 10:1 first gear ratio, the second with a 20:1 ratio. In first gear the first car would have 2000ft/lbs of torque at the rear wheels the second 4000ft/lbs. There would be no comparison in acceleration between these two cars (M Coupe to Yugo) even though they have the same torque.
The S54 engine has about a 20% increase in redline. If the same shift points (in mph) were kept with the new engine than we would see a 25% increase(new engine has 6% higher torque) in rear wheel torque in each gear. The car would be significantly faster in every condition. However, it appears that BMW has chosen to keep similar ratios, most likely for marketing reasons. By doing this the performance gains are solely the ability to hold the ratio longer, while not minor, it is much less than the alternative, in terms of quickness.
I can't get too irritated as I know I'll love the car anyway and I'm glad BMW even makes it. To be honest I'm surprised they even put the effort forward to put the new engine in considering they are ending the model after another 1 1/2 years of very limited production.
The part that bothers me is changing gear ratios (by changing them all or just the final drive ratio and 5th) is so easy and wouldn't cost more that a dime or two but was most likely torpedoed due to concerns about comparisons to the much heavier M3 or possibly a concern that it would be faster than the next M Roadster as the Z line is expected to gain weight.
Done.
Hugh
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