Soldato
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It's not torque doing that, it's power. Just the diseasel has more power lower down.
Stick a turbo on a petrol engine and the same thing happens.
Is Torque Overrated ?
- Thread starter Fr0dders
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It's not torque doing that, it's power. Just the diseasel has more power lower down.
Stick a turbo on a petrol engine and the same thing happens.
I'm going to guess 0-60 time will not really of changed at all...
my reasoning without going to swat up on wiki is bhp is derived from torque & rpm, and as you launch with revs screaming and clutch slippping looking at the graphs there is very little change. (maybe there will be a change due to fact power comes in sooner now and easier to launch though, who knows)
more torque at higher rpms = win
torque increases at low rpms = fail (which is why tractors and diesels are slow)
my reasoning without going to swat up on wiki is bhp is derived from torque & rpm, and as you launch with revs screaming and clutch slippping looking at the graphs there is very little change. (maybe there will be a change due to fact power comes in sooner now and easier to launch though, who knows)
more torque at higher rpms = win
torque increases at low rpms = fail (which is why tractors and diesels are slow)
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[TW]Fox;15190908 said:
Really?
E39 or 60?
So... Most modern 4cyl N/A petrol engines then?
My OMGVTECNOTORQUELOL Accord has less torque than a Civic/Accord Type R or an S2000, yet I can punt it around town nicely without having to redline it
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power is a mathmatical figure for "work done", torque is the actual force being applied
Soldato
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I don't know why people slate us diesel drivers so much. I like the torque but i'm not about to go racing some big petrol turbo'ed car because i'm under no assumptions that i'd stand a chance. I just find the diesel great for motorways due to overtaking power and economy and since i do a lot of town driving as well the torque is great for stop/start traffic compared to a lot of petrol cars i've driven which needed a good dose of pedal to keep from stalling, especially on inclines. If i wanted more performance i'd get another scooby or even buy something like my dads legacy which is one of those imports with the twinscroll turbo etc.. As for the noise, the 320D is quite quiet as was my 525D and the sound insulation inside the cabin is superb to the point i over rev the thing cause i forgot its a derv.
Exactly, diesels are brilliant for these sorts of applications - around town and on the motorway in the way they deliver their power. They are also more economical than their petrol equivalents, particularly in stop start traffic.
This unfortunately seems to be something that a lot of petrol die-hard fanboys deny.
but a diesel will have less overtaking power than a petrol car in general.. i just don't understand the facination with them
it's a illusion, yes you have a lot of torque at low revs giving the impression of 'the car can accel easy at low revs' ....but you only have low revs, which has knock on effect of giving you a lot less peak bhp. Driving your diesel at it's low revs is no different than thrashing a petrol car at high revs, apart from your not getting where your going as quickly
diesels just appear to be 'more', but they are less as far as performance and overtaking ability
they do make you feel like the car is being 'lazy' and 'easily handling a overtake', but thats just the nature of diesel, it's working just as hard.... if this were not the case your diesel would rev to 12krpm and make 1000bhp
edit: dont mean to be rude with above, but I can't see the attraction of them... or a single reason to have a diesel motor in a car, if you were ploughing a field or pulling a trailor all day maybe
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![[TW]Fox](/data/man-of-honor/2009.png){kind=avatar}
Exactly, diesels are brilliant for these sorts of applications - around town and on the motorway in the way they deliver their power. They are also more economical than their petrol equivalents, particularly in stop start traffic.
This unfortunately seems to be something that a lot of petrol die-hard fanboys deny.
I can't remember the last time a petrol owner denied diesels are more fuel efficient.
I still fail to understand the big deal about Motorway power. Just how often do you need to leave somebody for dust in 6th sitting at 80 on the M1?
that is what the difference is. the low down torque makes it easier to drive. not need to wait for the revs to build up before it "goes" and the way that torque delivery ramps up makes the car feel nippy. things like gearing and the lack of rev range stop it from being being fast for its equivalent engine size etc
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My new engine is out of breath by 4000rpm. It probably develops around 110hp but it's got enough torque to pull blocks of flats down. Just select another gear and let that lazy lazy grunt drag you down the road. I wouldn't say it lacks overtaking power but it does like a much wider spaced box than a high revver.
(petrol by the way)
(petrol by the way)
You can do this in a petrol car as well - I never need to shift down on the Motorway when I'm in a rush. They move out the way, accelerate away or use resume on cruise. It is completely true I cannot do this quite as quickly as a 530d and that the 530d has more performance in 5th at 70mph than my car but come on, its not a critical operation, is it? You don't NEED to be able to get back to 90 1.3 seconds quicker, do you? It makes no difference to your journey being able to accelerate back to 90 a second or two quicker on a Motorway trip. The people who do this are probably the people who complain about rubbish fuel consumption from a petrol, well don't drive everywhere with a digital throttle then. It's pointless.
When overtaking on a normal road where more time overtaking = more time exposed to danger? Hell yes, maximum performance is hugely important but in this sort of scenario you simply select a lower gear and then complete the maneouver even quicker than you would have done in the diesel.
People seem to think I'm some sort of rabid petrol fanboy. I am not. I like both types of engine, drive both types of engine often and see a place for both types of engine. There is even a diesel on my future car shortlist. However I like to think I'm realistic. A lot of the perceived performance benefits of the diesel are worthless in the real world. Thats not to say I'm blind to the benefits, there are many diesels I would recommend over petrols.
Want a 4 cylinder BMW? Get the diesel.
Want to buy any Mondeo? Get the diesel if you dont want the Titanium X turbo.
etc.
Honestly half this forum takes the mick out of me for apparently being an old man yet you then all extol the virtues of performance without having to change gear, how waft-tastic is that
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Since you haven't changed the gearing, the answer is fairly easy...
Everywhere you have more torque then before you will get more acceleration/thrust then before... Clearly in your case 2.6K-5K RPM is where your car should be quicker then before.. however...
Through the gears, i.e. redlining in each gear, you won't see that much difference I'd have thought, since you can see that when you change up at the redline, and no doubt it drops back to probably 4-5K RPM? the difference in power/torque isn't that huge in that range pre/post remap.
However, if you stuck in in top gear at 2,500 RPM on the motorway and accelerated, I'd expect it to be just about noticeably quicker then before... since you can see that you have more thrust then before..
It's obvious why torque is misunderstood, since gearing is the key factor that determines the thrust this generates at the wheels, but in your case you do have the same gearing before and after, so any increase in torque at a particular part in the rev range will directly equate to more thrust/acceleration, it should be that simple...
And it looks like you really should be changing gear a little earlier then previously, I'd say no later then 5750 RPM, as long as when you change up it drops you back down to no lower then 4K.. if your ratios are closer then that, you should change up even earlier... Redlining through the gears is not the way to go for you!
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Associate
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its the torque at the wheels that is most important as the actual measurement rather than made up flywheel figures , the gear box acts as a torque multiplier. if you had the same gearbox on a diesel and petrol you would really notice the difference 
its the torque at the wheels that is most important as the actual measurement rather than made up flywheel figures , the gear box acts as a torque multiplier. if you had the same gearbox on a diesel and petrol you would really notice the difference
You'd certainly notice how quickly you have keep changing gear and how low it's top speed is..
It's not 'at the wheels' you need to know, power is measured by the dyno at the wheels, it's the thrust vs speed that you really need to know.. that takes gearing/torque into account and shows the only real picture of how a car will accelerate at any given gear/speed..
Associate
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You'd certainly notice how quickly you have keep changing gear and how low it's top speed is..
It's not 'at the wheels' you need to know, power is measured by the dyno at the wheels, it's the thrust vs speed that you really need to know.. that takes gearing/torque into account and shows the only real picture of how a car will accelerate at any given gear/speed..
yes thats very true , the cascades show the true sprinting ability
[TW]Fox;15191957 said:Honestly half this forum takes the mick out of me for apparently being an old man yet you then all extol the virtues of performance without having to change gear, how waft-tastic is that
Well, you do now
