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      08-17-2008, 11:37 AM   #38
bruce.augenstein@comcast.
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Quote:
Originally Posted by J08M3 View Post
Of course the charts and formulas have a use. My point was directed at people who argue about one car being faster or better than another simply by comparing stats on paper.
I don't know about "better", but, as long as the data is accurate (and as long as all the pertinent data is there), such charts can tell most of us a bunch more than just having reams of data to look at - and can give a very good indication about which car is potentially quicker.

In addition, you can't reliably tell which car is faster by a stint behind the wheel of each. As a for instance, I'm pretty sure the Merc will feel faster than the bimmer to the driver, but with the auto, the bimmer will be very, very close.

In addition, charts can tell you things you will never be able to ascertain with test drives. As an example, take a look at the first chart. The first (and perhaps most obvious) thing you can ascertain is that the M3, if it had, say, a 9500 rpm rev limit, would be even faster than it is now. You can tell this because there is a major loss in acceleration when you shift to second gear. Just look at that vertical gap! If you could rev higher in first, you'd be filling that gap in. Even though thrust in first would be falling off a cliff, you'd still be quicker than if you were in second. There would also be advantages (although lesser ones) in the next couple of gears.

The second thing is that, if you were willing to abuse the machinery*, the six-speed car would be quicker to 60 than the auto, and might in fact still be with (or even ahead of) the auto at the quarter mile point. The idea here is that an early lead is very hard to overcome because, in a quarter mile drag race, you have very little time to first reverse the trend, and then overtake. I know BMW says the auto is quicker, and I'm quite sure it is under their test procedures, but what that first chart tells me is that, everything done perfectly, the six-speed car has the potential early advantage that might in fact even hold up through a quarter mile. Of course as mentioned, you'd have to do everything perfectly, which is clearly not possible on any consistent basis, especially if you're me.

Another item is that, from, say, 70 and up, it's all MDCT, pretty close to all the time.

Bruce

*Abusing the machinery means, in this case, launching from whatever rpm the track will hold, going instantly to the floor, and holding rpm constant at the clutch point until vehicle speed catches up with engine speed, at which point the clutch is finally all the way out. Then, it's just dab-pull, dab-push, dab-pull, attempting to keep deceleration times during each shift to a minimum by using the tiniest travel of the clutch pedal consistent with the actual ability to complete the shift, all of this with right foot on the floor. None of this hitting the floor with the clutch pedal stuff. If you can keep deceleration times at or slightly below two tenths during shifts, my contention would be that you very well may be able to postpone the inevitable, and hold off the wonderbox long enough to take the win light.

All this from a chart...

PS - This is not meant to denigrate the bimmer box. It's clearly the wave of the future. And in fact, pulling off a run such as I described might in fact be cause for breaking out the champagne and calling it a day.

Edit: PPS - As an incredible example of what a simple chart can tell you, take a look at this. Unbelievable.