Is torque really relevant?
Discussion
donkmeister said:
I would go further and say that throttle response on modern engines is often misleading under normal circumstances. All the mainstream brands do it... You pick up the car, you drive a couple of miles and think "this feels peppy!". Then you get to a sliproad, floor it and find that what you thought was a moderate press of the throttle was actually full throttle.
It's like they've figured out that most drivers never pushed the pedal all the way so maximum power demand is in the first half of the pedal travel.
So OP, whatever you try, make sure you actually floor it a few times on your test drive.
I agree. It's like they've figured out that most drivers never pushed the pedal all the way so maximum power demand is in the first half of the pedal travel.
So OP, whatever you try, make sure you actually floor it a few times on your test drive.
A lot of low to medium powered cars seem to give three-quarters throttle opening with the accelerator pedal pressed about one-quarter.
Some manufacturers even say things like 'this engine delivers more oomph than you'd expect'.
It makes cars feel livelier than they actually are.
V8RX7 said:
In simple terms the torque means that it doesn't matter what gear you're in, it just goes.
I ran a 330 petrol whilst a mate ran a 330d, in a race mine was slightly faster, in reality as a daily driver on the road, his was the faster car
Yes and I agree with this having had both a E90 330d and E90 330i(both auto). As a daily driver I much preferred the power delivery in the 330d(it always felt quicker even though it was a touch slower). I think that I would probably have liked the 330i more if it had a manual gearbox though. The auto was a poor match to the N/A engine for me. I ran a 330 petrol whilst a mate ran a 330d, in a race mine was slightly faster, in reality as a daily driver on the road, his was the faster car
Ah the old power versus torque nonsense argument. Power is usually calculated from torque. Attempting to differentiate between them is just silly.
The only thing that matters is excess torque at a given road speed in a given gear. Thats it.
Have lots of excess and you accellerate fast.
Have a little, and you accellerate slowly
Have none, and you stay at the current speed
Have a minus amount of excess torque, and you slow down.
Its really very simple...
Not including end to end gearing in the discussion just makes the whole power thing utterly fatuous.
Oh, and for the point of clarity -- "excess torque" means "how much excess torque do you have at the road surface once all losses (mechanical, plus wind resistance (so CDA not CD)) are subtracted from gains (engine torque at defined engine revs and throttle opening, plus gearing)
The only thing that matters is excess torque at a given road speed in a given gear. Thats it.
Have lots of excess and you accellerate fast.
Have a little, and you accellerate slowly
Have none, and you stay at the current speed
Have a minus amount of excess torque, and you slow down.
Its really very simple...
Not including end to end gearing in the discussion just makes the whole power thing utterly fatuous.
Oh, and for the point of clarity -- "excess torque" means "how much excess torque do you have at the road surface once all losses (mechanical, plus wind resistance (so CDA not CD)) are subtracted from gains (engine torque at defined engine revs and throttle opening, plus gearing)
John Locke said:
Baldchap said:
This tends to result in better throttle response and,
One quality which a diesel, indeed any turbocharged engine doesn’t have is good throttle response. For that a naturally aspirated or supercharged petrol engine is needed, or better, an electric motor.jhoneyball said:
The only thing that matters is excess torque at a given road speed in a given gear. Thats it.
Yes, but whilst that is directly related to neither peak flywheel torque nor peak flywheel power, peak flywheel power gives you a better approximation of it for the optimal gear than peak flywheel torque does. Which is why peak power to weight ratio is a far better indication of performance than peak torque to weight ratio. Ultimately in any given situation it doesn't matter whether you use power or torque because if you have all the information, they're directly translatable. However, if you are going to work with the severely limited data set which comprises of just "peak power" or "peak torque", power is a much more useful indication of performance.
Edited by kambites on Monday 6th July 10:34
How much power and torque is required to "Make Progress" ?
I used to use our Citroen C1 and to be honest, didnt arrive anywhere slower than in my M135i, it could be painful up hills but it got there, there is a happy medium to be struck where a car works adequately and then a bit more in normal driving/legal(ish) road speeds.
I think a modern 2 litre TDI is all the torque, flexibility and performance you would ever need, and a bit more, then you are into want and degrees of total overkill.
Makes me laugh when anyone says a car is dangerous due to a lack of power, er nope, maybe something fromt he 1930s like an Austin Seven isn't really fast enough to keep up with traffic but anything you can buy now isn't dangerous, thats whoever is driving it, if it can reach all speed limits then its not going to kill you.
Even non enthusiasts get annoyed with slow cars, its why diesels are so popular, even if the 0-60 doesnt sound that fast, on the road they perform well, I get the impression a lot cant believe anything could possibly be faster than their 140 bhp Golf.
EV's will take over like MC Bodge says, the same thing as when diesel did in the early nineties, it was only when actual viable models were available that suited normal punters that it happened. Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
I used to use our Citroen C1 and to be honest, didnt arrive anywhere slower than in my M135i, it could be painful up hills but it got there, there is a happy medium to be struck where a car works adequately and then a bit more in normal driving/legal(ish) road speeds.
I think a modern 2 litre TDI is all the torque, flexibility and performance you would ever need, and a bit more, then you are into want and degrees of total overkill.
Makes me laugh when anyone says a car is dangerous due to a lack of power, er nope, maybe something fromt he 1930s like an Austin Seven isn't really fast enough to keep up with traffic but anything you can buy now isn't dangerous, thats whoever is driving it, if it can reach all speed limits then its not going to kill you.
Even non enthusiasts get annoyed with slow cars, its why diesels are so popular, even if the 0-60 doesnt sound that fast, on the road they perform well, I get the impression a lot cant believe anything could possibly be faster than their 140 bhp Golf.
EV's will take over like MC Bodge says, the same thing as when diesel did in the early nineties, it was only when actual viable models were available that suited normal punters that it happened. Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
J4CKO said:
EV's will take over like MC Bodge says, the same thing as when diesel did in the early nineties,
Yes, favourable taxation. 
The 90s was a different time - the vast majority of cars were manuals and those cars which were were autos were generally slow and torque-sapping. These days with mainstream cars increasing going automatic and automatics being so fast to respond, the penalty for chaing gear (both in terms of time and, more crucially, effort) has all but disappeared. If you request significant acceleration from a modern automatic petrol or diesel, it will kick down; whether it's kicking down one or three gears is largely irrelevant to the driver.
Of course the torque gap between diesels and petrols has also fallen dramatically. When the comaprison was between a naturally aspirated petrol and a turbo diesel, the diesel could easily have three or four times as much torque. Now it's turbo vs turbo and diesels rev more freely, the difference tends to be in tens of percent rather than hundreds.
Edited by kambites on Monday 6th July 10:41
J4CKO said:
I think a modern 2 litre TDI is all the torque, flexibility and performance you would ever need, and a bit more, then you are into want and degrees of total overkill.
....
Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
I remember my Dad's mate getting a Golf TDI (90?) in 1994, and offering me a drive in it to demonstrate how good it was for a diesel. It had plenty of low rpm shove and gave good economy. ....
Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
My Mk4 Mondeo 2.0 TDCI was excellent all-rounder for normal (and even, surprisingly, autobahn) driving. A (good, not too compromised by emissions regs) modern 2.0 TD may have a bit more at the top end and overtaking, but for normal driving not a lot in it. 3.0+ doesn't really offer that much more utility.
Bring on the cheaper, good EVs.
cerb4.5lee said:
V8RX7 said:
In simple terms the torque means that it doesn't matter what gear you're in, it just goes.
I ran a 330 petrol whilst a mate ran a 330d, in a race mine was slightly faster, in reality as a daily driver on the road, his was the faster car
Yes and I agree with this having had both a E90 330d and E90 330i(both auto). As a daily driver I much preferred the power delivery in the 330d(it always felt quicker even though it was a touch slower). I think that I would probably have liked the 330i more if it had a manual gearbox though. The auto was a poor match to the N/A engine for me. I ran a 330 petrol whilst a mate ran a 330d, in a race mine was slightly faster, in reality as a daily driver on the road, his was the faster car
Newer 30d with auto box and xdrive absolute weapon of a car for point to point although nowhere near as engaging as a sorted E46 30i manual.
Best way I heard it explained;
BHP is how fast you hit the wall
Torque is how far you take the wall with you
Torque is important but not the be all end all. From my experience driving a 225bhp focus ST 5 pot and the FN2 Civic type R. Both similar power to weight, Civic was 200 but slightly lighter. Focus felt a fair bit faster as it had monster torque compared to the high reving R. Still I actually preferred the type R as a drivers car, but when I just wanted to get A to B with the least fuss, Focus for sure.
BHP is how fast you hit the wall
Torque is how far you take the wall with you
Torque is important but not the be all end all. From my experience driving a 225bhp focus ST 5 pot and the FN2 Civic type R. Both similar power to weight, Civic was 200 but slightly lighter. Focus felt a fair bit faster as it had monster torque compared to the high reving R. Still I actually preferred the type R as a drivers car, but when I just wanted to get A to B with the least fuss, Focus for sure.
J4CKO said:
How much power and torque is required to "Make Progress" ?
I used to use our Citroen C1 and to be honest, didnt arrive anywhere slower than in my M135i, it could be painful up hills but it got there, there is a happy medium to be struck where a car works adequately and then a bit more in normal driving/legal(ish) road speeds.
I think a modern 2 litre TDI is all the torque, flexibility and performance you would ever need, and a bit more, then you are into want and degrees of total overkill.
Makes me laugh when anyone says a car is dangerous due to a lack of power, er nope, maybe something fromt he 1930s like an Austin Seven isn't really fast enough to keep up with traffic but anything you can buy now isn't dangerous, thats whoever is driving it, if it can reach all speed limits then its not going to kill you.
Even non enthusiasts get annoyed with slow cars, its why diesels are so popular, even if the 0-60 doesnt sound that fast, on the road they perform well, I get the impression a lot cant believe anything could possibly be faster than their 140 bhp Golf.
EV's will take over like MC Bodge says, the same thing as when diesel did in the early nineties, it was only when actual viable models were available that suited normal punters that it happened. Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
That’s far too sensible an answer!I used to use our Citroen C1 and to be honest, didnt arrive anywhere slower than in my M135i, it could be painful up hills but it got there, there is a happy medium to be struck where a car works adequately and then a bit more in normal driving/legal(ish) road speeds.
I think a modern 2 litre TDI is all the torque, flexibility and performance you would ever need, and a bit more, then you are into want and degrees of total overkill.
Makes me laugh when anyone says a car is dangerous due to a lack of power, er nope, maybe something fromt he 1930s like an Austin Seven isn't really fast enough to keep up with traffic but anything you can buy now isn't dangerous, thats whoever is driving it, if it can reach all speed limits then its not going to kill you.
Even non enthusiasts get annoyed with slow cars, its why diesels are so popular, even if the 0-60 doesnt sound that fast, on the road they perform well, I get the impression a lot cant believe anything could possibly be faster than their 140 bhp Golf.
EV's will take over like MC Bodge says, the same thing as when diesel did in the early nineties, it was only when actual viable models were available that suited normal punters that it happened. Prior to about 1993 diesel models were horrible, slow taxi/farmer spec things which were only any good if you had free diesel. Will be the same with EV's when the price comes down and range goes up nobody is going to want a diesel.
My commute to work (when I was allowed to go to the office) took the same in my previous vRS diesel as it does in my current M140i. It was plenty brisk enough to get you in trouble with the bits in blue etc. It felt quicker than it really was due to the torque and third gear was pretty effective for overtaking.
I know there are much quicker cars than my 140, but even that’s a bit daft really. It gets to very illegal speeds with ease and you can’t really extend it much on the public roads.
RobM77 said:
(Noble M400 for example).
But that was using fairly old school turbochargers, easy to switch to much more modern ones. Apparently 
Boost threshold isn’t lag though, the distinction needs to be made. And yes on DBW lag, BMW, Mercedes, loads have it, and most of the diesels don’t appear to.
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