agree.
For what it is worth we have 2 diesels in the family and I drive them differently.
SWMBO - has a Mtsubishi that uses a VAG Derv. Hardly ever take up to the red line or over 4k rpm. Do occaisionally to give her a good work out.
I have a BMW 3 litre lump. 1st gear is, as mentioned, really for moving off. However where I find that I don't red line the VAG, I do find that my car is quite happy getting to the red line in 2nd and 3rd (when I need to get a shift on) but there is little point (so I don't do it) in 4th and 5th.
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"How do you drive diesels?"
Foot down hard. That's what I really like about diesels, you can have fun and still get amazing fuel economy. The very worst I've managed in mine is 45MPG. High 50's easy.
Megane 1.5 dCi - 30K and still going strong. Nothing broken at all. I think it responds better to hard driving, the engine seems smoother afterwards, probably the EGR valve getting cleaned out. [tempting fate now....]
Ride is dreadful though.
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Change up, change up, change up, change up, change up. Surf the torque wave and send yourself into a torpor with the monotony of life driving an oil burner.
Really, diesel cars are either tools for a job, or the realm of those that don't really like cars and driving.
Nose heavy, souless engine note, one trick ponys that fail to excite. I include in this cars like the BMW 535D although I'm yet to try a V8 diesel so I'll reserve judgement on those.
Doesn't diesel still cost more in the UK than petrol? Over here where it cost about 67p/ltr I can sort of see the point but for folks in the UK? I really don't get it.
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OldHand,
Dave A started the thread off by saying that he didn't want a debate on the pros and cons of petrol vs diesel.
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didn't want a debate onthe pros and cons of petrol vs diesel.
If we had an edit button I would go back and change my post then.
However, the relentless need to change up every second or so when accelerating hard and the fact the cars generally understeer a lot needs to be taken into account when driving a diesel.
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> However, the relentless need to change up every second
I can do a rapid 0-60 in TWO gearchanges. You speak twaddle.
------------------------------
TourVanMan TM < Ex RF >
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I've just switched too and its really easy to get used to - effortless power.
The one thing that sticks out is its rather pointless to rev it up to 5k as all the power is usually delivery by around 3.6krpm and Max torque is reached at around 2 - 2.5k. Changing at max power will put you back in the higher torque band in the next gear - should give you continued and sufficient shove.
2 other things to note, 1st gear is indeed a bit sloppy in most diesels and diesels drive exactly the opposite to a non turbo-d petrol. All the power and torque delivered early on and dying out by around 4k.
You want to sit at / or just below 2krpm for the best economy v performance - with this i get about 45MPG on my daily run driving normally which doesn't sound too hot but with 180bhp and 400nm or torque in a hatch it does well.
HF!
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Oldhand - clearly if you have nothing constructive to say why even bother.
I'm pretty fedup with the narrow minded and naive attitude towards diesel cars and engines. Theres absolutly no reason to slate diesel cars these days, some modern engines are extremely well developed and very well refined.
These days in the UK, diesel cars make up nearly 50% of all cars on the road. I've had turbo-d and supercharged petrol engines in the past both of which i loved but i've gone diesel now because it offered me more. You tootle along whinging about diesels and i'll remember how much fuel, insurance and tax it used to cost me to run them, then theres the hard ride and they weren't even that quick and thrilling.
If i buy petrol again it will be something real like an RS4 or an M3 not some diluted hot hatch that tries to be the next big thing.
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And also - the UK isn't a race track, you dont understeer in diesels and if you do your clearly going too fast.
I'll just buy an old BMW 3series or even better a NSX and just slide round bends all day. Again gearing in my hatch with 180bhp and 400nm isn't a problem.
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I have an RS4, 'a diluted hot hatch that tries to be the next big thing' and a rather nice 6 series tucked away in the garage and I've owned some so called 'sporty' diesels but that's neither here nor there.........
The question was 'how do you drive diesels'- the answer I gave is change up frequently through their rather narrow power band and be prepared for a lot of understeer. Whether that understeer comes on a wet roundabout, a bend where some other tractor driver has spilt his pig-fuel or during spirited driving is not important. What is important is to realise that a heavy weight over the nose compromises the car's handling and to my mind spoils enjoyment. I find enjoying my drive rather important- don't you?
Perhaps you regard recounting how you think you saved a few pennies to drive a mundane-mobile as some sort of compensation for that lack of enjoyment. Entirely your prerogative- I take the opposite view but I don't seek to silence your point of view..............
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Dave, Re max torque, look in the engine specs in the BMW glossy handout, or I guess ring the service desk.
Suggest you just change up early and dont think too much about it, you will adapt very quickly if you are a `thinking driver` and its obvious you are from posting the question in the first place..
Regards
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With most diesels (even CR), you don't get the same subtleties in accelerator response that you get with a petrol engine, so you'll quickly learn to be more aggressive with the throttle pedal. I don't mean you'll mash it to the floor all the time, but "feathering" the throttle in a lot of diesels is a waste of time. I guess a good way of putting it is that you need to be more deliberate with your throttle inputs. Once you crack this, a lot of the oft-quoted whinges about diesels feeling gutless becomes complete nonsense. The throttle pedal on a diesel engine is connected to a component that doesn't even exist in a petrol engine, so it's no wonder they behave differently.
I've done it the other way to you recently. Having driven 140k in the last 5 years in four diesel cars (Focus TDDi, Megane dCi, Mondeo TD, Scenic dCi), I've gone back to petrol temporarily (Fiesta 1.4), the first thing that struck me was the throttle response, and how a tiny input has a perceptible effect. This is why people say petrol engines feel more "alive", but with familiarity, so does a diesel. The second thing was the engine braking on the petrol engine - I find myself using the brakes much less on my rush hour commute. If I back off at 70 in the Fiesta, I'm doing 50 a few seconds later. If I back off at 70 in the Mondeo, I'm doing probably 65 in the same amount of time.
Peak torque on most diesels is between 1800 and 2200 RPM, and peak power between 4,000 and 4,500. Most pull well from 2k to 4k, and aren't difficult to keep in this rev range.
Finally, and the bit that surprises a lot of people is that most turbodiesels are not economical when driven hard. With the exception of the Megane dCi, all the cars above will go down below 35 mpg if thrashed.
Just like a petrol engine, the sweet spot on where a diesel engine does its best work is easily found by an intuitive driver. The pull from a good diesel when it's in that rev range can be genuinely exciting, and more than compensates for the limited rev range.
Cheers
DP
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The pull from a good dieselwhen it's in that rev range can be genuinely exciting and more than compensates for the limited rev range.
The problem is that the 'pull' is relatively short lived compared to a decent petrol engine and is interrupted by the need to change gear-yet again. I'd be genuinely interested to try a 'proper' high power diesel (ie something like the DMS 535D I had for a day) equipped with a V-AG DSG box.
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The pull in a petrol engine doesn't exist until you get to 4,000, or in some cases, over 5,000 rpm. So the evanescent "power band" is only accessible if you take it through the trough of despond. Driving a diesel with power gives the same accelerative ability (assuming similar outputs) at much more accessible and sedate engine speeds - rather like a large NA V8, but without the fuel penalty. Rarely do V8s require wringing by the neck to get decent power - so the turbo diesel substitutes for the cubes of the 4 litre lump. Which is usually of greater front-end load:)
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Oldhand - ok the pull is short lived but in a decent diesel 3rd and 400nm of torque can push me past anything in a blink. In my previous supercharged CTS i could achieve the same acceleration by all means and hold onto that gear longer but i would be going well over 70mph and breaking the limit in most cases (50 or 60mph).
Its the effortless driving within the law that is attractive running a modern day diesel with power. The equivelant petrol will also stay in gear longer but will take longer to overtake.
My point being, you can't break the limits these days in the UK there are too many cameras, too many police and too many radar detectors to risk it, let alone the fact that it is dangerous. Its a fair oppinon amongst many here that owning a powerful petrol car has its limits in the UK which makes owning a good diesel a great option.
I just spent nearly 20k on a new car, i could have bought and S4 or even stretched to a 2nd hand RS4 with finance but i view it as a waste of money with the state of the roads these days. I live near the countryside with some of the best roads in the UK and last weekend i encountered 3 speed traps in 2 days. You would loose your license driving an RS4 you dont get to drive it even close to its ability out of 3rd gear and if you did you will get caught out.
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...in a decent diesel 3rd and 400nm of torque...
Nitpicking alert.
400 nanometres? That won't get you far. I'm glad you're pleased with the T180 - assuming that's what you're describing - but you've quoted its maximum torque five times in this thread alone and I think we've got the message! And that's 400 Nm. SI units named after a person (watt, kelvin, newton etc.) are written in full with a small initial but abbreviated with a capital letter.
Nitpick over
}:---)
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Sorry OS - I miscounted. You quoted it three times, not five.
}:---)
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You're talking about a naturally aspirated petrol engine of small capacity. Not a valid comparison.
Let's take a blown 2.0 petrol from VAG that's used in my better half's car- it has significant pull from 2k revs and doesn't trail off until 6K. That's nearly double the power band of most diesels.
Move on to something like the RS4's V8 and it will pull hard from little over tickover right to the red line.
As yet there is no diesel engine I've experienced that comes anywhere close to these 2 units for flexibility and sheer verve.
Looking at something like the 535D which is meant to be one of the greatest current diesels it's a frustrating experience. Just as things start to get interesting the autobox shifts up as it's run out of steam. Reminds me of a succession of hard thuds in the back shoving you along. Sure it's effective but it's no fun at all and when you use the performance economy is only 4-5 mpg better than my RS4 at similar speeds.
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Try again:
"P.S. I'm not interested in a petrol vs diesel debate, plenty of that on other threads! "
The message will get through eventually.
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From a site re RS4: "Hi all im new to this forum, ive purchased a b5 rs4 but im not very happy with the mpg the car is returning, im getting 12-13mpg driving locally driving it normally, ok i know (when 1 buys one of these one shouldnt worrie about fuel) but cummon 12 mpg its a bit steep my 911 turbo 91 returned more than this. so if theres any body out there can can advice me pls help this car has had a MAF sensor about 1-1/2 years ago and there s nothing showing on vag com as faulty any help appreciated im sure these cars should return 18-22mpg locally"
Joke mpg, even when optimal! You cannot be serious about the 535 diesel consumption being only 4-5mpg better.
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Many thanks to all those that have given info relevant to the original post.
>>P.S. I'm not interested in a petrol vs diesel debate, plenty of that on other threads!
It seems to me that those who can't understand the original post are more interested in bragging about their own car (and possibly winding others up - yawn, yawn!) than making a contribution. Hijacking of threads, on any internet forum, just shows arrogance and rudeness IMHO.
Cheers,
Dave
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At the risk of being labelled a 'thread hijacker' and of 'boasting' I'll just add that the 535 I had for the day was showing 19mpg on it's fuel computer V the 14 I get when thrashing the RS4.
I'd also add that threads on internet forums do tend to develop.
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From a site re RS4: "Hi all im new to this forum ive purchased a b5 rs4 but im not very happy with the mpg the car is returning im getting 12-13mpg
Why would a comment about a B5 RS4 that you went searching the internet for be relevant to my comments? (FYI I have a B7 and it's totally different kettle of fish)
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The throttle pedal on a diesel engine is connected to a component that doesn't even exist in a petrol engine so it's no wonder they behave differently.
The other way around too, in that a diesel has no throttle for the pedal to be connected to.
All good posts here that mention keeping it around peak torque as a minimum. The right time to change gear depends on the car in question and number of gears - I'm not sure whether the 320d has a 5 or 6 speed box. What isn't always the case is the need to change up too early. I have an Octavia with a 6-speed box and in addition to the revs guidelines, a rough rule of thumb is one gear per 10mph as a maximum i.e. less than 30mph then no higher than 3rd, 40mph then no higher than 4th, etc It's good driving practice in any car according to the IAM, but I find driving at 30 in 4th means you will tend to head for 35mph to get the engine more comfortable.
My parents have recently gone from a Civic with a 1.4 petrol 5-speed to a Civic 2.2 CDTI 6-speed. With both of them driving it this weekend, I had to keep telling them to give it more revs because they both kept labouring it, using the same change points as the 1.4.
Although I partly agree with DP in that you should be aggressive with the accelerator, if you are crusing at peak torque then it can still be responsive to light inputs. I find the Skoda will surge forward when flooring the pedal when cruising in the right gear, but in general, NA petrols when in the right gear for cruising don't do much until the revs build up.
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I agree with James and others about peak torque - I drive a diesel automatic and that I think is what the CVT transmission is trying to ensure. It worked perfectly in the Audi 2.5 I used to have - it's all right in the current Mercedes B-class except that infuriatingly it revs up to 2000 rpm if you want to make any sort of progress from rest - just like a London taxi in fact.
My first diesel was a Golf estate (manual) and the 'one gear per 10 mph' method was just right for that as with James's Octavia. It's a pleasant challenge to get it right - far from boring, and I'm tempted to go back to a manual next time. I must try a DSG transmission for longer as this certainly seems to suit VAG diesel engines.
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I find half this debate mind stretching.
People enjoy driving a petrol engine hard but complain about chnaging gear on a deisle cos of the limited rev range.
I thought one of the enjoyments of driving was changing gear faultlessly and quickly.? (at least I find it so...
And if I acclerate from 2,250 rpm in 3rd to 4,000rpm I'm at the legal limit anyway.
Judging from some of the comments speed limits do not apply to some drivers .
( I could rant on about the Impreza doing 50mph in a 30mph limit past our house and the school 100 metres down the road - at 8:15am.. but I will not... some contributors sound like that tho:-(
madf
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Agreed, Madf. My diesel - with a mere 340 Nm of torque };---) - will pull in 3rd from barely 10 mph to 80 or so. OK, it grumbles a bit at first and would rather be in second until 20, but even so that requires only one gearchange from pootling speed to 'Good morning, sir. Is this your car?'.
And yes, OH, a megabudget petrol V8 might do it with more polish and decorum, but that amounts to solving a problem by throwing money at it, and there's nothing polished about that. And as for 'only 5 mpg' difference between a thrashed 535d and a similarly thrashed RS4, the other way to express that is that the 535d uses a third less fuel given the same treatment.
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It uses a third less fuel and gives less than a quarter of the enjoyment is a more accurate way of expressing it.
Looking at the small budget argument (as you seem to find a comparison between 2 mid range cars unnaceptable) you can compare the 2.0ltr PD140 VAG engine to it's 2.0ltr Petrol Turbo equivalent. The diesel is a very heavy unit that destroys the handling finesse of the car while having a 2k revs power band and being rough as the proverbial badger's backside. The petrol unit is light and effecient and sounds great when you rev it. You can achieve 38mpg at cruise V 49 in the diesel. It's also a hell of a lot more powerful and faster in whichever car it's installed in. Also the diesel will cost you more to buy in the first place- that get's you a whole load of fuel. I know which I'd choose.
Also I wouldn't assume everyone on this forum lives full time in the UK, some of us spend a lot of time in more enlightened places.............
I'm doing my best not to have a petrol v diesel debate but some people seem to want to continue it.
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Does the max tourqe figure (or rather where it tends to appear in the rev range) depend on the gearing of the car?
PS Oldhand - I think that you have made your point. Also DaveA doesn't really seem to want to hear your point on "his" thread so if you want to
start a thread I would like to contribute there
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> Does the max torque figure (or rather where it tends to appear in the rev range) depend on the gearing of the car?
No, it's the other way round. The torque curve (output against rpm) is a characteristic of the engine itself and its ECU map. The gearing is then chosen (or should be!) to translate this into usable performance on the road. Diesels typically have higher gear ratios because of their high-torque/low-revs characteristics.
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If you are new to diesels, the other thing to bear in mind is that they do benefit from almost red-lining (say 4,500 to 5,000 rpm) a couple of times a week (once they are run in). This seems to clear any soot build-up in the system and helps achieve maximum performance. Alternatively a nice long high speed run (on German Autobahns) does wonders.
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And then of course there is chipping to consider ...
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Get yourself a Octavia 140bhp diesel with DSG, pop it in sport mode on floor it......my god the thing shifts and changes gear so quickly the power never has a change to subside. Brings a smile to my face and a pound chest.....why did I wait this long to have my first diesel car?
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