I think I may have had a misunderstanding about terminology. When I wrote wheel torque, I thought that meant the torque x gearing = torque applied to the drive wheels (torque transmitted into the tires). From what you wrote, it seems that wheel torque is not torque at the drive wheels, but torque at the FLYWHEEL. Is this correct? Not being an automotive engineer, I think I got a little confused about the terminology.
I understand your point about wanting your next shift to be in the area of the torque/power output curve nearest max power. What is a little confusing to me is that because of the gearing, isn't first gear pretty much always delivering more torque (at the tires) than second gear under all parts of the curve?
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Originally Posted by The HACK
You're right that it shouldn't be subjective, but you're wrong that it's wheel torque that accelerates the car. It's actually torque X gearing multiplier.
This topic has been debated ad nauseum, with a ton of mis-information out there. The simple answer is, you want as much power delivered to the wheels for as long as possible. And most cars are designed to deliver the majority of their power at or near redline, and even on cars that see significant drop-off in power at or near redline, they're designed to deliver MORE power sooner in the next gear, or at least closer to peak power RPM, for longer, if you shift into the next gear at or close to redline.
So even if someone argues, well, the engine isn't making more power after, say, 5,800 RPM so there's no need to shift at 6,500 RPM? Wrong. There's plenty of good reason to shift at 6,500 RPM. One being the NEXT gear you will start closer to max power engine speed rather than trying to spool up that magical HP for another 800 RPM.
It's the area under the power curve through the gears that gives you the maximum acceleration.
Here's a good brain teaser for you. The 335D produces SIGNIFICANTLY more torque than the 335i. Yet is significantly slower to 60 mph and 1/4 mile. Think about that for a minute.
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