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How are diesel cars better than just normal petrol cars? Watch

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    Cheaper to run by a long shot in most cases (I changed my car to diesel of the same model and more than halved my fuel bill)

    Sometimes cheaper to tax

    But NOT as fun as a petrol car at all. If money wasn't an issue, I'd have petrol anyday.
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    (Original post by Lara C.)
    they have alot of torque, are more reliable and more efficient. however that comes at the cost of being heavy, low-revving and polluting.
    polluting?
    diesel cars have much lower CO2 emissions than petrol cars, which also means lower road tax
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    (Original post by Friggerpants)
    Each have their own benefits.

    Diesels - Run on veggie oil if you want, very reliable (no spark plugs etc), Lazy power.

    They sound ****, and the older ones are steel which is heavy, however most modern diesel blocks are light now
    You can't run a modern diesel engine on veggie oil any more. Which is a disgrace. Rudolph Diesel meant for his engine to run on peanut oil. Something to do with it clogging up the injector valve for the inlet manifold. Get an old defender 110 and your sorted though.

    Although you don't have spark plugs, glow plugs do go after a time and you won't be able to start the car in colder weather once they're gone. Though you could feasibly use a hair drier to get the same affect.

    To the OP

    The advantages of diesel engines. The fuel goes further, so it may cost you less. Some engines can be run on things like peanut/veggie oil. Torque curve, although that is only a consideration if you want to tow things and go off-roading in a 4X4. There are far less electronics and less to go wrong with it (compression ignition vs heat ignition in a petrol engine). This also means that provided that the air intake doesn't draw water in the engine will run under water. Hence why you see 4X4s with "snorkels." You can drive in a higher gear than you would be able to in a petrol because of the extra torque. There is also red diesel but that would be illegal on the road.

    Disadvantages.

    Noise they make. Its like a bucket of bolts. Acceleration can be sluggish and the top speed hindered. The fumes smell really bad. They can take longer to start in colder weather because the glow plugs have to warm the chambers or compression ignition won't work. Although this is a very short time in modern diesel engines. Diesel is more expensive to buy than petrol, litre for litre. Though a diesel litre tends to go further.
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    Bear in mind if you're buying a car from new/nearly new and the diesel car costs more to buy then it's a false economy in most cases unless you're doing mega miles.
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    (Original post by Neo Con)
    Oh yeah Lara if you had a 1.7 honda diesel (isuzu engine) and you got it remapped from 100 to 140 bhp, would you do the brakes? Companies told my friend not to and it seems to be the norm. They say "80 mph will always be 80mph" but surely you accelerate quicker so need to stop quicker?
    they are correct, 80mph in the same car is 80mph in the same car you have to stop. 100-140bhp is hardly anything special anyways, fair enough its a big improvement but 140bhp is nothing in the grand scheme of things.

    but it depends on the brakes that are currently fitted, if they are rubbish like the ones that were standard on my R400 then id uprate them with or without the power upgrade,
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    (Original post by munn)
    polluting?
    diesel cars have much lower CO2 emissions than petrol cars, which also means lower road tax
    i take it youve never seen what comes out the back of a diesel exhaust?

    diesel cars produce alot more nitrogen oxide, resulting in smog.
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    To all those who have said they are noisy/heavy etc. They really aren't any more. Driving a brand new diesel fiesta at the mo and it's SO quiet. (Better than any petrol car I know) and is really nice to drive. Plus manoeuvers are 'easier' to control
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    (Original post by lilangel890)
    To all those who have said they are noisy/heavy etc. They really aren't any more. Driving a brand new diesel fiesta at the mo and it's SO quiet. (Better than any petrol car I know) and is really nice to drive. Plus manoeuvers are 'easier' to control
    I dont know about the noise, in fact i agree modern diesels are nothing like the older ones. but they are still heavy;

    1.4 (08) Fiesta Petrol - 966kg
    1.4 (08) Fiesta Diesel - 1011kg

    the diesel has added 45kg, that alot of weight considering the entire engine in my car (K series) only weights 110kg. thats would equate to a ~50% weight increase.
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    Thats mostly because the block has to be made of iron not aluminium
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    (Original post by Entangled)
    I'm driving my ma's diesel right now. I'm finding it smooth actually - it's quite a forgiving setup between the engine and the clutch. There's power there in abundance, so it probably outguns quite a few pertol cars.

    I like the fact that they're low-revving. Doesn't do much for power, but I like to be in a high gear for the speed most of the time.
    I agree with most of this

    I learnt to drive in a Diesel and find that, Diesel's are much more harder to stall but they start jumping if you're in a high gear for the speed you're going at (well mine did). I've heard they're more economical, they don't require as much revs either

    I wouldn't mind either way which engine I have TBH, wouldn't be a factor in buying a car lets just say that but I'm no massive car enthusiast.
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    (Original post by WilliamWJ)
    **** diesel. petrol is smoother, nicer to drive, more entertaining, and fuel consumption isnt that much of an issue with new petrol cars. You have to drive diesel cars 'harder' to get the same out of them as 'normal' driving would with a petrol of the same power/torque etc.

    did anyone see the fifth gear test recently where two of the same car, one 1.2 petrol, one 1.4? diesel did the same route, and the petrol came out with a better mpg?

    plus diesel fumes smell nasty and petrol doesnt
    At last some less tech talk. one of the few answers that made sense lol
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    (Original post by fosters88)
    not only that but it was said the petrol car was more torquey.

    I'm not that techy when it comes to cars, what I have read is diesel cars have more torque a low revs. But surely that depends on the engine?
    e.g. 8v engines produce higher torque at low revs to that of 16v engines.


    anyways I do remember reading something which proved diesel actually does more harm to the environment than petrol. Regardless that diesel may produce less co2 emisisons, diesel actually churns out more nasty stuff into the atmosphere.
    Lucky for diesel drivers, the road-tax people have not grasped this yet....
    haha lol. gd info
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    (Original post by WilliamWJ)
    i hate driving diesel cars. i used to have a 1.5 dci 2002 clio and it was meant to be a very 'refined' engine. you could tell it was a diesel. driving my mums 1.4 turbo A3 is sooo much nicer.

    ever been stuck behind a smelly old diesel van? closing off the air vents in your own car still does not get rid of that nasty oil burning smell.
    Ah right, so that 1.5 clio was an accurate representation of all diesel engines then? Comparable to a 3.0 derv unit in a 3 series? A TDV8 in a Range Rover?

    No, it was a ****** little engine in a cheap little car, hence it wasn't much cop to drive. I doubt you'd 'hate' driving either of the examples above, or indeed any of the prestige models built with diesels. They wouldn't put diesels in cars like that if they were no good to drive.

    There's a fair bit of nonsense being spouted on here, the simple fact is that the reason diesels are so popular is that they offer superior fuel economy (although you have to travel a certain amount of miles a year to save any money, to offset the price premium charged for a diesel over it's petrol equivalent.)

    And I'm not a derv fanboy either, both my cars are petrol.
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    (Original post by Lara C.)
    they are correct, 80mph in the same car is 80mph in the same car you have to stop. 100-140bhp is hardly anything special anyways, fair enough its a big improvement but 140bhp is nothing in the grand scheme of things.

    but it depends on the brakes that are currently fitted, if they are rubbish like the ones that were standard on my R400 then id uprate them with or without the power upgrade,
    I see. I just thought he would have to, it's almost an increase of 50% BHP, despite 140 bhp not being much overall. For example, all "rover shaped civics" have same brakes whether they are 1.4,1.5,1.6, only the 1.8 has bigger brakes. So what is the point of the 1.8 civic having bigger brakes? After all it's only 166 bhp compared with 100 bhp of the 1.4?

    I don't know how the brakes are on the ep civic. I'll ask him some questions.

    Also lots of people who have VW Golf and remapping them are having clutch or engine problems. Because the 1.9 diesel engine is already giving out 150 bhp which is alot for it's size.
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    (Original post by WilliamWJ)
    i hate driving diesel cars. i used to have a 1.5 dci 2002 clio and it was meant to be a very 'refined' engine. you could tell it was a diesel. driving my mums 1.4 turbo A3 is sooo much nicer.

    ever been stuck behind a smelly old diesel van? closing off the air vents in your own car still does not get rid of that nasty oil burning smell.
    But you're comparing a cheap French hatchback with a new premium brand car. The Audi is probably worth about 8 times more than the Clio, i'd be pretty disappointed if there wasn't a difference!

    I'm not saying the diesel would be more refined than that petrol, but if you drove a 2L TDI common rail A3, then you'd have a much different experience compared with the Clio, especially since the Audi will have much better sound insulation and lots of torque.

    Although at the end of the day it's just personal preference I guess.
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    (Original post by zKlown)
    I learnt to drive in a Diesel and find that, Diesel's are much more harder to stall but they start jumping if you're in a high gear for the speed you're going at (well mine did). I've heard they're more economical, they don't require as much revs either

    I wouldn't mind either way which engine I have TBH, wouldn't be a factor in buying a car lets just say that but I'm no massive car enthusiast.
    And I agree with this. Funny how the world works.
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    For the same power, diesels are faster in everyday conditions, ie without revving them up to 5000+ rpm. Less need for a downshift to overtake etc.

    But a petrol is probably faster for the same power if you don't mind going to town on the revs, as there is less need to shift gear as you can go all the way to 6000 or so but in a diesel it's like 4500.
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    Over the weekend, me and my friends went to the WOMAD festival. Me, plus 4 teenagers, plus 5 teenagers' worth of festival stuff (nearly up to the roof in the boot) in my 20 year old Land Rover with a 2.5 turbo diesel. 130 miles there. On the way home we had an extra person so 6 people, and the stuff was again nearly up to the ceiling in the boot, another 130 miles home. 260 mile round trip, and I still have more than half a tank left. Cost me about 35 quid. If anyone would like to tell me they can do 260 miles with 5/6 people and enough stuff to fill a Defender 110 on £35 with a petrol engine then please, go ahead :p: Oh, and with very little noticeable drop in performance either. That said, we were doing 60-65mph on the slow lane the whole way up on the M5 and M4, occasionally 70 when racing artics. Not that noisy either, we had the music loud enough to drown out the engine and we could still talk. Great fun

    Edit: I'm running on BFG ATs too, not mud tyres certainly, but definitely not as smooth rolling as road biased tyres.





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    (Original post by Nuffles)
    Over the weekend, me and my friends went to the WOMAD festival. Me, plus 4 teenagers, plus 5 teenagers' worth of festival stuff (nearly up to the roof in the boot) in my 20 year old Land Rover with a 2.5 turbo diesel. 130 miles there. On the way home we had an extra person so 6 people, and the stuff was again nearly up to the ceiling in the boot, another 130 miles home. 260 mile round trip, and I still have more than half a tank left. Cost me about 35 quid. If anyone would like to tell me they can do 260 miles with 5/6 people and enough stuff to fill a Defender 110 on £35 with a petrol engine then please, go ahead :p: Oh, and with very little noticeable drop in performance either. That said, we were doing 60-65mph on the slow lane the whole way up on the M5 and M4, occasionally 70 when racing artics. Not that noisy either, we had the music loud enough to drown out the engine and we could still talk. Great fun

    Edit: I'm running on BFG ATs too, not mud tyres certainly, but definitely not as smooth rolling as road biased tyres.






    HAHA that is quality :bban:
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    (Original post by Nuffles)
    Over the weekend, me and my friends went to the WOMAD festival. Me, plus 4 teenagers, plus 5 teenagers' worth of festival stuff (nearly up to the roof in the boot) in my 20 year old Land Rover with a 2.5 turbo diesel. 130 miles there. On the way home we had an extra person so 6 people, and the stuff was again nearly up to the ceiling in the boot, another 130 miles home. 260 mile round trip, and I still have more than half a tank left. Cost me about 35 quid. If anyone would like to tell me they can do 260 miles with 5/6 people and enough stuff to fill a Defender 110 on £35 with a petrol engine then please, go ahead :p: Oh, and with very little noticeable drop in performance either. That said, we were doing 60-65mph on the slow lane the whole way up on the M5 and M4, occasionally 70 when racing artics. Not that noisy either, we had the music loud enough to drown out the engine and we could still talk. Great fun
    A new Volvo V50 can do twice that distance with the same amount of fuel...

    You used about 8.43l/100km; the above (unloaded) does 3.9l/100km.
 
 
 
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