RE: Porsche rolls out 680hp wagon
Discussion
rob.e said:
So how big is the boot then?
They should come up with some sort of "boot to torque" ratio.. see if they can get one up on audi with that one too.
It's amazing isn't it that an article about an estate car doesn't actually feature a single photo of the boot. They should come up with some sort of "boot to torque" ratio.. see if they can get one up on audi with that one too.
here you (and everyone) go:
Please show us all the relevant photos when writing an article PH.
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Torque is a force, and force applied to a mass makes acceleration, F=MAPower is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
hi court said:
Are jaguar doing xfr wagon yet?
Really can't see why you would buy one if you need an estate, and if you don't need an estate why not just buy the normal panamara?
Rs6 gets my vote. Or this, if only it was a foot longer.
Jag don't even do an XFR! Big gap. Hottest XF is the 380ps 'S'.Really can't see why you would buy one if you need an estate, and if you don't need an estate why not just buy the normal panamara?
Rs6 gets my vote. Or this, if only it was a foot longer.
bertie said:
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Torque is a force, and force applied to a mass makes acceleration, F=MAPower is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
E65Ross said:
bertie said:
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Torque is a force, and force applied to a mass makes acceleration, F=MAPower is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
Anyway...stepping away from the GCSE physics...nice estate car.
bertie said:
E65Ross said:
bertie said:
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Torque is a force, and force applied to a mass makes acceleration, F=MAPower is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
I'm not saying torque isn't important, far from it. I've just been saying that torque/weight is utterly meaningly, which it is, because it doesn't take gearing into account; whereas power to weight does....
Nanook said:
.....
Yes it is.bertie said:
Torque is a force
No it's not, so the rest of your post is wrong."Torque is defined as a twisting force that tends to cause rotation."
https://www.collinsdictionary.com/dictionary/engli...
E65Ross said:
Does anyone else spot the flaw in that sentence? You've actually said it's NOT about power, and then you have put in brackets that effectively it IS about power.
I'm not saying torque isn't important, far from it. I've just been saying that torque/weight is utterly meaningly, which it is, because it doesn't take gearing into account; whereas power to weight does....
Torque is the force applied and that is what accelerates a mass.I'm not saying torque isn't important, far from it. I've just been saying that torque/weight is utterly meaningly, which it is, because it doesn't take gearing into account; whereas power to weight does....
Power is the rate of work done and the result of the force applied.
Both torque and power figures quoted by manufacturers are flywheel so don't take account of gearing.
bertie said:
E65Ross said:
Does anyone else spot the flaw in that sentence? You've actually said it's NOT about power, and then you have put in brackets that effectively it IS about power.
I'm not saying torque isn't important, far from it. I've just been saying that torque/weight is utterly meaningly, which it is, because it doesn't take gearing into account; whereas power to weight does....
Torque is the force applied and that is what accelerates a mass.I'm not saying torque isn't important, far from it. I've just been saying that torque/weight is utterly meaningly, which it is, because it doesn't take gearing into account; whereas power to weight does....
Power is the rate of work done and the result of the force applied.
Both torque and power figures quoted by manufacturers are flywheel so don't take account of gearing.
You'll generally find that cars with a higher power to weight will be faster accelerating than those with a lower power to weight. That same correlation cannot be said of torque to weight at all. If it was, every diesel would be faster than anything with a high revving, zingy petrol engine. Torque, in the latter instance, is definitely relevant, because as you say, POWER is related to torque and rpm (it revs higher....produces more work with less torque and is thus quicker), but torque to weight as a standalone ratio is meaningless.
bertie said:
Torque is a force, and force applied to a mass makes acceleration, F=MA
Power is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
Example time using your requirements to calculate acceleration.Power is work done in a given time.
The gearing affects the torque at the wheels, so yes engine torque, gearing and mass determine acceleration.
I have a 1:1 ratio gear.
My car weighs 1 tonne.
My engine produces 200 lb ft of torque at an unknown rpm
How fast does it accelerate?
Can you not see the rpm the torque is created is important? What you want is a number that combines the rpm and the torque.
stuartrav said:
Does anyone know the co2 emissions figure? If under 50 it will make for a very attractive company car just like my Volvo XC90 T8 Hybrid. Under 50 is the holy grail and will make the car a bargain and will probably mean 99% will be sold as company cars.
The normal Panamera 4 hybrid is 59g, the Panamera Turbo S Hybrid (this one) is 69g on the Porsche website.Would be a great company car option but £140k basic....
Edited by bertie on Wednesday 27th September 15:18
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Because ......The engine produces the same torque, but the torque at the wheels is reduced when you choose a higher gear. So you accelerate more slowly in a higher gear, but you travel faster (as you accelerate) and as you do so the power increases with (speed / rpm)
I'm afraid that most of the others contributors are correct. Torque gives you the acceleration, and the power produces goes up with the speed or RPM. which is why you see on a graph of them against RPM, that power as an upward slope and torque tends to be flat as revs increase. The engine twist remains fairly constant (if you measure it with a machine) but the power produced ( by the speed) increases the faster you go. It can be hard to fully appreciate and is more complicated when gearboxes are included. but torque to weight is really the important figure you need to know.
hughclinton said:
E65Ross said:
If it's all about torque and nothing to do with power, how come a car with a dead flat torque curve from 1500rpm-6000rpm accelerates up a steep hill faster in 2nd gear from 5000rpm at 30mph than it does from 4th gear at 2000rpm? It'd producing the same torque, so why would one accelerate quicker in a lower gear if it's all about torque and not power? The gearing has no effect on the peak torque the engine is producing, but it does effect the power output to the wheels.
Because ......The engine produces the same torque, but the torque at the wheels is reduced when you choose a higher gear. So you accelerate more slowly in a higher gear, but you travel faster (as you accelerate) and as you do so the power increases with (speed / rpm)
I'm afraid that most of the others contributors are correct. Torque gives you the acceleration, and the power produces goes up with the speed or RPM. which is why you see on a graph of them against RPM, that power as an upward slope and torque tends to be flat as revs increase. The engine twist remains fairly constant (if you measure it with a machine) but the power produced ( by the speed) increases the faster you go. It can be hard to fully appreciate and is more complicated when gearboxes are included. but torque to weight is really the important figure you need to know.
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