No - the correct term *is* power when talking about that commodity. BHP is just one of the units in which it is measured - along with kW and PS.
Just as "speed" is a valid term - or velocity if you also want to specify the direction of travel - regardless of whether you are measuring it in MPH, KPH, FPS, etc.
Torque is irrelevant to performance. I know it's hard for you to understand, and it doesn't agree with your prejudices, but it's true.
For a car with a gearbox - and that is all of them - to get highest performance you ignore peak torque, and keep the engine at maximum power, or as close as you can get.
You can easily see this if you just work out the torque at the gearbox output for these two cases
400nM at 2000RPM
200nM at 5000RPM with ratios chosen to give the same speed at the output shaft - the higher revs, lower torque will give you 25% more torque at any given output speed of the gearbox.
It's true that if you can't change gear you'll get the highest acceleration at peak torque. But that is not relevant to getting the highest performance.
If you compare cars with similar peak torque outputs, but different power outputs the performance won't match. But if you look at cars with similar power outputs, but different torque outputs the figures will match.
While I agree it is not entirely irrelevant to performance it is a consequence of engine power and it's ability to supply the energy to the car ending up in kinetic energy.
It would be similar to claiming that the speed of sound is dependent on temperature.
While peak power is an indicator of engine power, the acceleration calculation would be of the form:
For the 528i, energy of car at 62mph (0.5 x m v^2) = integral(0 to
6.2s) of Engine Power(t) dt
where engine power is that supplied at any instant of the acceleration test.
I might agree that maximum acceleration in any gear would occur at the maximum engine torque in that gear, the fact in itself is most unhelpful in determining 0 to 60mph times.
That's only true for a manual transmission. At the risk of being accused by you know who of introducing another red herring, as soon as you insert a torque converter between the engine and gearbox, your cosy relationship goes out the window! So we ignore that, and assume that we have a conventional manual transmission.
They're not, actually. They get considerably less steep in each successive gear.
Gearbox output torque vs road speed graphs are essentially the same shape in each gear but are, of course, scaled differently.
This is where we go round in circles! It's true that peak acceleration in each *gear* coincides with the engine's peak torque. But, in many cases, you can obtain a *higher* acceleration at a given road speed by using a different gear and running the engine at max power.
That acceleration will be lower than you would get in that 'different' gear at peak engine torque but it would be at a higher road speed. For maximum accelerative performance you need the maximum available acceleration all the way up the speed range - so you need to run the engine as close to max power as possible.
Try reading the post I was replying to before continuing. Which you've conveniently snipped. Here it is:-
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Ah! I see your problem now. If, as you've seemingly posed the question, we're discussing, "When does the maximum instantaneous acceleration over the operating rpm range of the prime mover occur in any *one* gear ratio at a time?", then the answer to *that* question *will indeed* be at maximum torque rpms.
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Which makes it pointless you commenting on my post, since you simply can't accept the basic principle of doing the test in only one gear.
And in the original discussion, 0-60 times weren't mentioned. Just the point in an engine's output where the best acceleration occurred. Which of course is at maximum torque, not maximum BHP.
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