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Are my sums correct here

  • 22-05-2007 10:25am
    #1
    Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭


    just on the whole diesel v petrol thing i decided to do a rough calc on what i would have saved if i bought a 530d instead of a 530i.

    1 gallon = 4.546 litres

    25mpg petrol = 5.5 mp/l

    35mpg diesel = 7.7mp/l

    10,000 miles in a year requires 1,818 litres of petrol

    @ 1.15 per litre equals 2,090euro

    10,000 miles per year requires 1,298 litres of diesel

    @ 1.06 per litre equals 1,376 euro

    saving is circa 700.

    Is that correct? not really an issue for me as a) i wont do 10000 miles this year so the gap decreases and b) if i do much mileage its business and ill get 1.20 or so per mile.

    Its not as big a gap as youd think tho and i certainly wouldnt trade the straight 6 petrol howl :D


«1

Comments

  • Registered Users, Registered Users 2 Posts: 2,178 ✭✭✭Irish Wolf


    Cyrus wrote:
    just on the whole diesel v petrol thing i decided to do a rough calc on what i would have saved if i bought a 530d instead of a 530i.

    1 gallon = 3.785 litres

    25mpg petrol = 6.6 mp/l

    35mpg diesel = 9.24 mp/l

    10,000 miles in a year requires 1,515 litres of petrol

    @ 1.15 per litre equals 1,742 euro

    10,000 miles per year requires 1,082 litres of diesel

    @ 1.06 per litre equals 1,146 euro

    saving is circa 600.

    Is that correct? not really an issue for me as a) i wont do 10000 miles this year so the gap decreases and b) if i do much mileage its business and ill get 1.20 or so per mile.

    Its not as big a gap as youd think tho and i certainly wouldnt trade the straight 6 petrol howl :D

    1gallon = 4.546l unless you live in the U.S. ;)


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    fixed ;)


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    Cyrus wrote:
    fixed ;)

    Sounds about right, but my 2.0L car gets on average 46mpg, so 12.15 mp/l so that is 823litres at approx 1.06 is 872.38.
    Also I do 30,000 miles per year, so that is €2617 for diesel.

    If your 530i was to cover the same mileage than you are looking at €5226.

    that is €2609 per year more than fuel. And if you are to keep a car for an average of 3 years, than the saving is going to be €7827. Plus a 3 year old 2.0l diesel car with 90K is going to fetch a few quid more, or be more saleable than a 3 year old 3.0L petrol with 90K.

    So, if yo are doing low mileage, then the differenc is not huge, but if you are doing bigger mileage, then a circa 2.0L diesel makes FAR more sense.

    Also, diesels are far better to drive.


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    prospect wrote:
    Sounds about right, but my 2.0L car gets on average 46mpg, so 12.15 mp/l so that is 823litres at approx 1.06 is 872.38.
    Also I do 30,000 miles per year, so that is €2617 for diesel.

    If your 530i was to cover the same mileage than you are looking at €5226.

    that is €2609 per year more than fuel. And if you are to keep a car for an average of 3 years, than the saving is going to be €7827. Plus a 3 year old 2.0l diesel car with 90K is going to fetch a few quid more, or be more saleable than a 3 year old 3.0L petrol with 90K.

    So, if yo are doing low mileage, then the differenc is not huge, but if you are doing bigger mileage, then a circa 2.0L diesel makes FAR more sense.

    Also, diesels are far better to drive.

    far better to drive than what? and iwas comparing 3l diesel to 3l petrol


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    Sounds about right, but my 2.0L car gets on average 46mpg, so 12.15 mp/l so that is 823litres at approx 1.06 is 872.38.
    Also I do 30,000 miles per year, so that is €2617 for diesel.

    If your 530i was to cover the same mileage than you are looking at €5226.

    that is €2609 per year more than fuel. And if you are to keep a car for an average of 3 years, than the saving is going to be €7827. Plus a 3 year old 2.0l diesel car with 90K is going to fetch a few quid more, or be more saleable than a 3 year old 3.0L petrol with 90K.

    So, if yo are doing low mileage, then the differenc is not huge, but if you are doing bigger mileage, then a circa 2.0L diesel makes FAR more sense.

    Also, diesels are far better to drive.
    Your maths are correct but miss the point. Two supposedly equivalent cars, one petrol, the other diesel, cost not an awful lot different to run, unless you are doing huge mileage. BTW, I completely disagree with your last statement. Diesels sound worse, have worse throttle response and are generally heavier engines for the same power, their only real benefit is efficiency. There is a reason that there aren't any true sports cars with a diesel engines.


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  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    nastysimon wrote:
    Your maths are correct but miss the point. Two supposedly equivalent cars, one petrol, the other diesel, cost not an awful lot different to run, unless you are doing huge mileage. BTW, I completely disagree with your last statement. Diesels sound worse, have worse throttle response and are generally heavier engines for the same power, their only real benefit is efficiency. There is a reason that there aren't any true sports cars with a diesel engines.

    Well,

    Missed what poit exactly, my whole equation was based on doing 30,000 miles, so that was the very point. Summed up by my second last line???

    RE: Diesel driving. it is personal preference, isn't it.

    I prefer diesel, thats why I said it, and your argument of 'sounds worse' 'throttle response' is the same dated, misinformed rubbish i hear being spouted by some incoherent auld fellas in my local on a friday night. I am sure you prefer the drive of a petrol, but at least drive a modern diesel before coming out with that kind of drivel.

    As for a true diesel sports car, http://en.wikipedia.org/wiki/Audi_R10 , where have you been?


  • Registered Users, Registered Users 2 Posts: 66,122 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    Cyrus wrote:
    Its not as big a gap as youd think

    Indeed. In your case you'd need to do big miles to recoup the higher second hand price of the 530d had you bought one of them

    Big engined petrol cars are bargains in Ireland :D


  • Registered Users, Registered Users 2 Posts: 7,044 ✭✭✭Wossack


    prospect wrote:
    Well,

    Missed what poit exactly, my whole equation was based on doing 30,000 miles, so that was the very point. Summed up by my second last line???

    RE: Diesel driving. it is personal preference, isn't it.

    I prefer diesel, thats why I said it, and your argument of 'sounds worse' 'throttle response' is the same dated, misinformed rubbish i hear being spouted by some incoherent auld fellas in my local on a friday night. I am sure you prefer the drive of a petrol, but at least drive a modern diesel before coming out with that kind of drivel.

    As for a true diesel sports car, http://en.wikipedia.org/wiki/Audi_R10 , where have you been?


    So what makes diesels far better to drive then petrol? :confused:


  • Closed Accounts Posts: 1,435 ✭✭✭C_Breeze


    Wossack wrote:
    So what makes diesels far better to drive then petrol? :confused:


    a thing called torque


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    Wossack wrote:
    So what makes diesels far better to drive then petrol? :confused:

    Holey Moley,

    Are you trying to make a perfectly stright forward point more confusing?

    Try reading this bit again:
    prospect wrote:
    RE: Diesel driving. it is personal preference, isn't it.

    I prefer diesel, thats why I said it,


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  • Registered Users, Registered Users 2 Posts: 4,183 ✭✭✭Fey!


    As well as a higher purchase price, you also have higher maintainence costs. I think that the break even for petrol/diesel is usually aroud 17,000 miles.

    That said, the 530 diesel is supposedly quicker than the 530 petrol, can be chipped, and has more torque, as well as using less of a cheaper fuel.

    Finally, as a friend of mine says, if you can't afford to run it, don't buy the car.


  • Registered Users, Registered Users 2 Posts: 7,044 ✭✭✭Wossack


    prospect wrote:
    Holey Moley,

    Are you trying to make a perfectly stright forward point more confusing?

    Try reading this bit again:

    try not to jump down my throat - your first point stated it as fact, not as opinion. Your second post made that clear, but not the basis of your opinion.

    Thats all my question was about, what do you prefer about diesels? Sorry if it was construed as hostile :o


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    Wossack wrote:
    try not to jump down my throat - your first point stated it as fact, not as opinion. Your second post made that clear, but not the basis of your opinion.

    Thats all my question was about, what do you prefer about diesels? Sorry if it was construed as hostile :o

    At the time you posted, you had read both my posts, and therefore knew that I was expressing my opinion only.

    You then asked:
    Wossack wrote:
    So what makes diesels far better to drive then petrol?
    which is a different question than:
    Wossack wrote:
    what do you prefer about diesels?

    so to answer your question,

    I prefer the "extra torques" as per Mr Clarksons dictionary of motoring. I prefer the power delivery in the mid range. I prefer the less effor required in the gears if you want a lazy drive. I prefer the economy. I prefer paying less at the pumps. I prefer almost everything about them. I really see very few advantages a modern petrol car has over a modern diesel, except when you go into supercar territory, and even then, they are not much use in our country.


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    prospect wrote:
    At the time you posted, you had read both my posts, and therefore knew that I was expressing my opinion only.

    You then asked:

    which is a different question than:


    so to answer your question,

    I prefer the "extra torques" as per Mr Clarksons dictionary of motoring. I prefer the power delivery in the mid range. I prefer the less effor required in the gears if you want a lazy drive. I prefer the economy. I prefer paying less at the pumps. I prefer almost everything about them. I really see very few advantages a modern petrol car has over a modern diesel, except when you go into supercar territory, and even then, they are not much use in our country.

    well the only part of that argument that relates to driving is the torque, which plenty of petrol engines have in abundance esp any turbo ones as extra torque is normally due to the turbo not the fuel


  • Registered Users, Registered Users 2 Posts: 21,263 ✭✭✭✭Eoin


    I won't say that my diesel engine doesn't sound quite rough, but it certainly isn't bad to drive. Personally I like the pick-up at low revs, and I don't find it slow to react; there is very little lag at all.

    I can see why people wouldn't like one, but I have a feeling that a lot of perceptions are based on their experience with much older engines.

    When you look at the old BMW 320cd, new 335d, Alfa GT (and Brera I think), Octavia RS TDI cars coming out, you can see that diesel is becoming a viable fuel for sporty cars, not just long distance cars.
    unkel wrote:
    Indeed. In your case you'd need to do big miles to recoup the higher second hand price of the 530d had you bought one of them

    Big engined petrol cars are bargains in Ireland:D

    The 530D is more likely to get a better resale price than the 530 as you have alluded to, so he probably wouldn't have to do huge mileage.


  • Registered Users, Registered Users 2 Posts: 66,122 ✭✭✭✭unkel
    Chauffe, Marcel, chauffe!


    eoin_s wrote:
    The 530D is more likely to get a better resale price than the 530 as you have alluded to, so he probably wouldn't have to do huge mileage.

    Good point. I suppose it depends on the age of the car in how far that is true. New they cost the same, so it makes much more sense to buy the diesel (which nearly all 530 buyers do these days). Lower depreciation and lower fuel costs

    From my point of view as a last owner (well, not last owner but the one that's going to depreciate the car until it's not worth much really), it's higher depreciation (as the higher purchasing price will depreciate to zero) and lower fuel costs


  • Posts: 3,620 ✭✭✭ [Deleted User]


    You really have to put serious effort to get anything like the manufacture say.

    My bmw with a 6cyl 2.5l gets as low as 21 mpg on my daily drive to work if I drive normaly. 6 miles main road then as much as 10min stop start driving that gets me the remaining mile.

    Keeping it in a lower rev range, A/C etc off, no bursts of strong acceleration can yield 27+ on the same trip.


  • Registered Users, Registered Users 2 Posts: 4,266 ✭✭✭MercMad


    That said, the 530 diesel is supposedly quicker than the 530 petrol, can be chipped, and has more torque, as well as using less of a cheaper fuel.
    ...........didn't TopGear disprove that myth quite conclusively !!

    Either way.............if it were me and I was doing anything over 10,000 I would buy the 530D over the 530i, or the E320Cdi over the E350, puelry for the turbo torque !

    However I would never, repeat NEVER buy a 4 cylinder diesel car, they just sound cack !!

    I find the above Merc & BMW 6 cylinder diesels sound quite nice actually, and for me that is a big consideration when selecting a car to drive ! Its called enjoyment !


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    the 194 bhp of the 530d loses out to the 231 bhp of the 530i in nearly every instance.

    proof here:

    http://www.fastsaloons.com/


    wouldnt fancy replacing a turbo on the 530i either!


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    Well,
    Missed what poit exactly, my whole equation was based on doing 30,000 miles, so that was the very point. Summed up by my second last line???
    The point was that unless you are doing the miles, it doesn't make sense. Comparing your much less powerful 2.0 diesel with his 3.0 petrol makes no sense, it is not a fair comparison.
    RE: Diesel driving. it is personal preference, isn't it.
    Perhaps, though those cars which are most about driving are very rarely diesel. Similarly, those cars which are driven by those least worried about fuel consumption are also rarely diesel. I have driven a few modern diesels, some of which are considered class leaders, but the truth was that they lacked the driving satisfaction of their petrol brothers. The fuel economy was important for the owner, but were it not, the petrol would have been the prefered choice.
    I prefer diesel, thats why I said it, and your argument of 'sounds worse' 'throttle response' is the same dated, misinformed rubbish i hear being spouted by some incoherent auld fellas in my local on a friday night. I am sure you prefer the drive of a petrol, but at least drive a modern diesel before coming out with that kind of drivel.
    As I said, I have. If diesels sounded better, wouldn't those very people who go most for driving pleasure build diesel cars; the sports car manufacturers. The throttle response of a well sorted petrol engine is better than that of a well sorted diesel. That is not to say that the pick-up of a diesel at low revs is not as good or better than a petrol, just that the time to respond to one pressing the throttle is slightly worse (unfortunately, most petrol engines are getting worse at this, so soon you're opinion might actually be correct for the average). BTW, if it is drivel, please point to a learned source that says so. Otherwise, my experience backs up my assertion, so I'm not going to change my opinion just because you decide to resort to calling it drivel.
    As for a true diesel sports car, http://en.wikipedia.org/wiki/Audi_R10 , where have you been?
    For most of the time, I've been in Ireland. Even I, who it seems spouts drivel, knows that it's not a sports car, it's a race car. I hope you too can tell the difference. The ACO have a set of rules for the 24 hours of Le Mans which stipulates the restrictor sizes for various engines. The larger the restrictor the more power the car can make. Diesel engines are allowed to have larger restrictors than petrol engines, so the rules favour them.


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  • Posts: 3,620 ✭✭✭ [Deleted User]


    nastysimon wrote:

    For most of the time, I've been in Ireland. Even I, who it seems spouts drivel, knows that it's not a sports car, it's a race car. I hope you too can tell the difference. The ACO have a set of rules for the 24 hours of Le Mans which stipulates the restrictor sizes for various engines. The larger the restrictor the more power the car can make. Diesel engines are allowed to have larger restrictors than petrol engines, so the rules favour them.

    Are ya sure? Restrictions in WRC effectivly mean a cap on BHP. According to an article I read through turbo charging and magic I don't quite understand they can hugely increase torque.

    Maybe the same restrictors favour the torquey diesel engine. More energy per unit less air required ect ect.


  • Closed Accounts Posts: 118 ✭✭nastysimon


    ronoc wrote:
    Are ya sure? Restrictions in WRC effectivly mean a cap on BHP. According to an article I read through turbo charging and magic I don't quite understand they can hugely increase torque.

    Maybe the same restrictors favour the torquey diesel engine. More energy per unit less air required ect ect.
    Yes, I'm certain. For a supercharged (including turbo-supercharged) diesel engine, you can have one 55.9mm restrictor or two 39.9mm ones. For a supercharged petrol engine you can have one 45.3mm or two 32.4mm restrictors with more than 2 valves per cylinder, or one 46.8mm or two 33.4mm ones with 2 valves per cylinder. Thus a petrol engine with a turbo could produce 50% more bhp with the restrictor that a diesel has rather than the standard petrol multivalve one. That sounds like a big advantage to me.
    What happens is that the restictor allows air through it at the speed of sound, which means that there is an absolute limit to how much air one can get through the restrictor, resulting in an absolute power limit. With turbos and very large normally aspirated engines, one can get this maximum power for a very large part of the rev range, ultimately giving lots of low down torque (bhp=revs x torque). This ideally suits diesels as they opperate in that rev band, but if diesels had the same restrictors as petrol engines, they would not be competitive.

    For reference:
    http://www.lemans.org/sport/sport/reglements/ressources/auto_2007/regl_2007_prototype_ACO_fr_gb.pdf


  • Closed Accounts Posts: 1,253 ✭✭✭Sandwich


    nastysimon wrote:
    ultimately giving lots of low down torque (bhp=revs x torque).

    Can someone here please explain in laymans language why 'torque' matters. It seems to in most discussions, so I guess it does, but have never understood why it is quoted.

    bhp=revs x torque, so is bhp not the best indicator of a car's pullingpower/acceleration capability(or bhp/weight of car).
    Everything else being equal, will the higher bhp car not beat the lower bhp car for pulling power. Even if it has lower max torque, does that just not mean that it will be turning at a higher rpm, than the one with more torque? i.e. does the matching of gear ratios to a given engine not take account of the different torque/speed characteristics of the engine, and still leave bhp to the wheels the important measure.

    Appologies to the cognoscenti if I'm missing the blindingly obvious.


  • Registered Users, Registered Users 2 Posts: 7,722 ✭✭✭maidhc


    Sandwich wrote:
    Can someone here please explain in laymans language why 'torque' matters. It seems to in most discussions, so I guess it does, but have never understood why it is quoted.

    A car with higher torque will deliver its power from the sheer force of the engine as distinct from the speed at which the crank is turning. So while a diesel may be able to overtake safely in 4th at 1500rpm, a petrol of similar bhp is likely to need second an 2x/3x the RPM.

    A diesel is a lazier car to drive, but gives the impression of having more power as there is far more grunt available in the higher gears. In everyday driving (e.g. going up hills, overtaking on the N7 and so forth) there is less of a need to stir the box, and IMO driving is a more relaxed affair.

    Its horses for courses though. I much rather the engine in my bosses MB s600, than my focus diesel, but I get about 40MPG more than he! But he can afford it, and I still get to drive it sometimes!


  • Closed Accounts Posts: 1,253 ✭✭✭Sandwich


    Thanks maidhc. So is torque a misleading figure to be getting excited about (except for those too lazy to change gear).

    The other car might have more torque, but as long as you are prepared to revyourengine/changedown, if you have more power, you have the quicker car ?


  • Registered Users, Registered Users 2 Posts: 7,722 ✭✭✭maidhc


    Sandwich wrote:
    Thanks maidhc. So is torque a misleading figure to be getting excited about (except for those too lazy to change gear).

    The other car might have more torque, but as long as you are prepared to revyourengine/changedown, if you have more power, you have the quicker car ?

    Pretty much my understanding of it anyway. Mind you the power may be at 8000rpm, and thus less "available" than it may be in a diesel.

    Interestingly the yanks were big into slow revving petrols with loads of torque and a couple of gears before the automatic became popular.


  • Closed Accounts Posts: 118 ✭✭nastysimon


    Sandwich wrote:
    Can someone here please explain in laymans language why 'torque' matters. It seems to in most discussions, so I guess it does, but have never understood why it is quoted.

    bhp=revs x torque, so is bhp not the best indicator of a car's pullingpower/acceleration capability(or bhp/weight of car).
    Everything else being equal, will the higher bhp car not beat the lower bhp car for pulling power. Even if it has lower max torque, does that just not mean that it will be turning at a higher rpm, than the one with more torque? i.e. does the matching of gear ratios to a given engine not take account of the different torque/speed characteristics of the engine, and still leave bhp to the wheels the important measure.

    Appologies to the cognoscenti if I'm missing the blindingly obvious.
    I'm afraid that I've yet to come across a very simple explanation.
    The first thing you have to realise is that an engine produces different amounts of torque (and therefore power) throughout its rev range. This means that a car which does 200bhp, maximum, may only do 50bhp at 2000rpm, but 200 at 8000rpm (that is actually a case where it produces the same amount of torque at both). Diesel cars generally don't rev to high revs, they can't. Most cars produce maximum power near to their maximum revs. So a diesel which produces 200bhp at 4000rpm will be producing twice the torque of the petrol engines which needs to get to 8000rpm. Thus, the aforementioned 200bhp diesel at 4000rpm will be able to accelerate as hard as the aforementioned 200bhp petrol at 8000rpm as power determines one's ability to accelerate.
    This of course assumes the same power for both, which is rarely the case. So long as your power is through a useable power band, more power will be quicker when driving hard (as in racing).
    Since diesels use a lower rev range than petrols, they have to produce more torque to get the same amount of power. One of the advantages of this is that in a diesel you often drive closer to maximum power and well into the useful power band. In a petrol, you are more likely to be driving well below the maximum power for most driving, in fact you may be well outside the useful power band for quick driving in a petrol, often requiring you to drop a gear to accelerate as hard as the guy in his diesel. That said, to go from gentle cruising to accelerating really hard in either will require that you drop one or more gears, at which point the petrol's ability to rev higher and, most likely, greater power will make it the quicker.
    Therefore, diesels give a more relaxed drive and better economy. A petrol is better for spirited driving, has better acustics (less clatter, more aurally pleasent when driven hard), more power and a considerably lighter engine. For really relaxed driving where economy is no object, huge petrol engines are best of all as they are more refined, give smoother power delivery and will pull hard from the off.


  • Closed Accounts Posts: 2,669 ✭✭✭mukki


    this is my take on petrol vs diesel, might be completey wrong but it makes sense to me


    diesel
    because of the high compression ratio (+ turbo + faster speed means less time to leak by the cylinder rings) they will blow the head gasket if the ecu doesn't reduce the ammount of fuel injected as the speed increase. because of this they have huge torque from 1200-2500, this gives you an illusion that the diesel car is stronger then a similar bhp petrol,

    petrol
    because the same air leaking past the cylinder rings leaves less oxygen to burn fuel the ecu cuts back fuel to save the enviroment, at higher speed there is less time for leakage, so the ecu can add more fuel (compression ratio is small in petrols so head gasket is safe upto about 7,000 then its time for the ecu to cut back)

    diesel are for economy or heavy loads !
    petrol for speed and power (although pretty economical if ya have 6 gears)


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    mukki wrote:
    petrol for speed and power (although pretty economical if ya have 6 gears)

    Don't agree.

    In everyday driving on nearly all roads in this country, in nearly all conditions, including 'spirited' driving on country roads, most 1.9Turbo Diesels will be a far better solution than an equivalent 2.0 Petrol, in terms of ease of driving and suitable amounts of available power when it is required.

    If you are on a race track in a sports/race car (essentially the same thing pedantic pat), then a petrol may be a better option.
    That said, I personally drove 2 Alfa 156's in mondello at a promotional event. One was a 1.8Petrol the other a 1.9Turbo Diesel. From my personal experience (not age old hear-say) of comparing these two cars, the diesel was far better and faster on the track, fact. It didn't seem faster, or give a false impression of power, it quite simply was the better engine on the day.


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  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    but the 1.9jtd is much more powerful engine than the 1.8ts? its not a fair comparison


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    Don't agree.

    In everyday driving on nearly all roads in this country, in nearly all conditions, including 'spirited' driving on country roads, most 1.9Turbo Diesels will be a far better solution than an equivalent 2.0 Petrol, in terms of ease of driving and suitable amounts of available power when it is required.

    If you are on a race track in a sports/race car (essentially the same thing pedantic pat), then a petrol may be a better option.
    That said, I personally drove 2 Alfa 156's in mondello at a promotional event. One was a 1.8Petrol the other a 1.9Turbo Diesel. From my personal experience (not age old hear-say) of comparing these two cars, the diesel was far better and faster on the track, fact. It didn't seem faster, or give a false impression of power, it quite simply was the better engine on the day.
    A sports car and a race car serve very different purposes. A race car is designed to be as quick as possible, a sports car is designed for driving pleasure and may not be all that quick (the 1.6 Mazda MX-5 was a good sports car, but hardly fast). Whether you put them on a track or not makes no difference. If you think that they are essentially the same thing, you really are deluding yourself.

    Ok, firstly you are comparing a turbo with a normally aspirated engine. Secondly, the 1.9jtd is a 1910cc engine, so it is classified as a 2.0 for tax. The 1970cc petrol engined 156 (the one in the same tax category) is considerably quicker. So, while the 156 1.9jtd might be as quick when driven by a good track driver as a 156 1.8ts (despite weighing 40kg more, most like due to the engine), it has 160 more cc and a turbo to help it.

    It really doesn't matter, for sports cars, spirited driving and sheer driving pleasure, a good petrol engine is preferable to a diesel engine.


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    Cyrus wrote:
    but the 1.9jtd is much more powerful engine than the 1.8ts? its not a fair comparison

    True,

    So by the same rationale, comments like:

    Diesel is for towing trailers
    and
    Petrol is for raw speed

    are also not a fair comparison.

    I want to tow a trailer, I think I'll buy a BMW 335D M sport.
    Oh, and for a raw power spin around the track, a 1.oL Chev Matiz should do the job.


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    nastysimon wrote:
    , while the 156 1.9jtd might be as quick when driven by a good track driver as a 156 1.8ts
    It was FAR quicker
    nastysimon wrote:
    It really doesn't matter, for sports cars, spirited driving and sheer driving pleasure, a good petrol engine is preferable to a diesel engine.
    This is where we differ in opinion.


  • Registered Users, Registered Users 2 Posts: 12,822 ✭✭✭✭galwaytt


    nastysimon wrote:
    Ok, firstly you are comparing a turbo with a normally aspirated engine. Secondly, the 1.9jtd is a 1910cc engine, so it is classified as a 2.0 for tax.

    It really doesn't matter, for sports cars, spirited driving and sheer driving pleasure, a good petrol engine is preferable to a diesel engine.

    No, and No.

    I drove a GT 1.9JTD on test, when I had a TT, when shopping for a replacement. The GT pulled better, accelerated better (seat of the pants dyno....;) , and was easier to cover ground, briskly in. Used less juice, too. lower-stress hi-po drive, if you will.

    Both turbo's, both 4-pots, and, on paper the TT should win, bhp-wise. Naturally, stats on paper aint what it's about.........

    Ode To The Motorist

    “And my existence, while grotesque and incomprehensible to you, generates funds to the exchequer. You don't want to acknowledge that as truth because, deep down in places you don't talk about at the Green Party, you want me on that road, you need me on that road. We use words like freedom, enjoyment, sport and community. We use these words as the backbone of a life spent instilling those values in our families and loved ones. You use them as a punch line. I have neither the time nor the inclination to explain myself to a man who rises and sleeps under the tax revenue and the very freedom to spend it that I provide, and then questions the manner in which I provide it. I would rather you just said "thank you" and went on your way. Otherwise I suggest you pick up a bus pass and get the ********* ********* off the road” 



  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    so (im assuming its the 180 tt) a 180 bhp 173 ft/lb petrol that accelerates from 0-60 in roughly 7.5 seconds felt slower than a 148bhp 225 ft/lb diesel that has a 9.5 sec 0-60.

    pants dyno seems off :confused:


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  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    prospect wrote:
    True,

    So by the same rationale, comments like:

    Diesel is for towing trailers
    and
    Petrol is for raw speed

    are also not a fair comparison.

    I want to tow a trailer, I think I'll buy a BMW 335D M sport.
    Oh, and for a raw power spin around the track, a 1.oL Chev Matiz should do the job.

    and where were those comments made? i quoted yours exactly, you are making stuff up!

    dont get me wrong the 1.9jtd is a nice engine and reasonably spritely, but its not a quick car and it still has a diesel clatter and narrow power band


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    Cyrus wrote:
    and where were those comments made? i quoted yours exactly, you are making stuff up!

    I am summarising, but here is one quote:
    mukki wrote:
    diesel are for economy or heavy loads !
    petrol for speed and power
    Cyrus wrote:
    still has a diesel clatter and narrow power band

    Not really, I would say it is a bit noisey on a cold morning when it is warming up, but sitting in the car you would not notice.
    Also the power band is ideal for most Irish driving situations, hence my preference for diesels.

    It is all well and good saying petrols are faster off the mark, and under hard accelleration the longer range of 1st and 2nd gear are better, but that is not really useful in this country, unless you want to get arrested/killed.


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    It was FAR quicker
    This could be for a multitude of reasons, I can't explain completely, but for one to be "FAR quicker", it would want to have been much more powerful, or driven by a better driver, or had racing slicks while the other was on road tyres, etc. A little power differential would have very little difference on the track.
    This is where we differ in opinion.
    Yes, you and I differ. So do you and the established motoring press, engineers, etc. I'm on their side until I get some slightly more convincing argument.
    galwaytt wrote:
    Both turbo's, both 4-pots, and, on paper the TT should win, bhp-wise. Naturally, stats on paper aint what it's about.........
    Well, actually, when it comes to speed, that's what it is about. If you can't demonstrate that the Alfa was quicker and show the numbers to prove, you really don't have a leg to stand on. The Audi might have felt slower, but it wasn't. That said, the Alfa probably was a more relaxed drive, it's also not a sports car, which would help explain that too.


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    prospect wrote:
    I am summarising, but here is one quote:




    Not really, I would say it is a bit noisey on a cold morning when it is warming up, but sitting in the car you would not notice.
    Also the power band is ideal for most Irish driving situations, hence my preference for diesels.

    It is all well and good saying petrols are faster off the mark, and under hard accelleration the longer range of 1st and 2nd gear are better, but that is not really useful in this country, unless you want to get arrested/killed.

    the car is well insulated and damped to keep the noise from intruding too much but the noise is there, and as to the usefulness of petrols being faster off the mark etc surely thats only your opinion? hasnt got me killed or arrested yet


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    I am summarising, but here is one quote:




    Not really, I would say it is a bit noisey on a cold morning when it is warming up, but sitting in the car you would not notice.
    Also the power band is ideal for most Irish driving situations, hence my preference for diesels.

    It is all well and good saying petrols are faster off the mark, and under hard accelleration the longer range of 1st and 2nd gear are better, but that is not really useful in this country, unless you want to get arrested/killed.

    It's noise is also less plesant when pressed hard. The roar of the petrol engine is much nicer to the ear. And that diesel clatter can be heard whenever you go to overtake.

    Also, being quicker under hard accelleration is not dangerous, it is safer. It allows you to overtake quicker and therefore safer. Being able to get to the speed limit faster is safer and not illegal or likely to get yourself killed.


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  • Registered Users, Registered Users 2 Posts: 2,326 ✭✭✭ciarsd


    What an interesting thread.

    As regards 1.8 T Spark vs 1.9JTD comparisons - there is none. I owned and drove both, JTD wins hands down.
    You don't have to keep revs high and constantly check gears pre-manoeuvre, the power is at hand in all gears.

    The JTD (IMO and quite a few VW PD driving workmates I've had this discussion with) agree that the JTD is far quieter than the VW PD range and is one of the quietest on the market.
    The paper stats are pretty even for the JTD vs PD, but this means nothing on the road. I've not driven a PD150 so cannot comment, I have however driven a couple of PD130's.. one which was remapped (allegidly - didn't feel any different).
    Sure it's not got the characteristics of a large cc'd straight 6 petrol, but what do you expect when making a chalk and cheese comparison.

    Sure it doesn't have the refinement of a 6-Pot diesel, but the price differences make this an unfair comparison.

    IMO the only reason the JTD has a crap paper 0-100km is because you need to pull 3rd gear for it to get there, whereas with petrol engined equivalents, this can be achieved with 2nd.

    Cyrus, were you considering the 330D/530D when choosing your new car? Interesting thread for justification.


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    nastysimon wrote:
    This could be for a multitude of reasons, I can't explain completely, but for one to be "FAR quicker", it would want to have been much more powerful, or driven by a better driver, or had racing slicks while the other was on road tyres, etc. A little power differential would have very little difference on the track.
    They were both standard road going versions, driven by the same driver, me. Almost everyone that drove them had the same opinion, and their times also confirmed, the diesel was FAR quicker. Stop trying to pick fault where none exists..



    nastysimon wrote:
    Yes, you and I differ. So do you and the established motoring press, engineers, etc. I'm on their side until I get some slightly more convincing argument..
    So by this statement you mean that your OPINION is better, or more qualified than mine!! What an arrogant person you are.


    nastysimon wrote:
    Well, actually, when it comes to speed, that's what it is about. If you can't demonstrate that the Alfa was quicker and show the numbers to prove, you really don't have a leg to stand on. The Audi might have felt slower, but it wasn't. That said, the Alfa probably was a more relaxed drive, it's also not a sports car, which would help explain that too.
    I don't need figures to back up my opinion. You have obviously no interest in what others think, and I can see you are the type of person who always considers themself right.
    Also my argument is not about speed (read the posts), it is about how the engine is more suitable for driving in everyday situations. Maybe you consider accelerating away from the lights and 'beating' a family in a diesel MPV who have no interest in 'racing' you to qualify you as a "petrol head". I consider that selfish and irresponsible.


  • Registered Users, Registered Users 2 Posts: 4,787 ✭✭✭prospect


    nastysimon wrote:
    Also, being quicker under hard accelleration is not dangerous, it is safer. It allows you to overtake quicker and therefore safer. Being able to get to the speed limit faster is safer and not illegal or likely to get yourself killed.

    Off the mark, it is purely for high testoterone, low brain level, tennage childishness.

    In the mid range, when safe overtaking is the issue, 9 out of 10 Turbo Diesels will easily out perform a similarly sized petrol engine.


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    ciarsd wrote:
    What an interesting thread.

    As regards 1.8 T Spark vs 1.9JTD comparisons - there is none. I owned and drove both, JTD wins hands down.
    You don't have to keep revs high and constantly check gears pre-manoeuvre, the power is at hand in all gears.

    The JTD (IMO and quite a few VW PD driving workmates I've had this discussion with) agree that the JTD is far quieter than the VW PD range and is one of the quietest on the market.
    The paper stats are pretty even for the JTD vs PD, but this means nothing on the road. I've not driven a PD150 so cannot comment, I have however driven a couple of PD130's.. one which was remapped (allegidly - didn't feel any different).
    Sure it's not got the characteristics of a large cc'd straight 6 petrol, but what do you expect when making a chalk and cheese comparison.

    Sure it doesn't have the refinement of a 6-Pot diesel, but the price differences make this an unfair comparison.

    IMO the only reason the JTD has a crap paper 0-100km is because you need to pull 3rd gear for it to get there, whereas with petrol engined equivalents, this can be achieved with 2nd.

    Cyrus, were you considering the 330D/530D when choosing your new car? Interesting thread for justification.

    i hope this isnt gone way off topic, and im not looking for a row, it is an interesting thread :)

    i dont think anyone is trying to compare the 1.8ts to the 1.9jtd, the 2.0 jts would be a fairer comparison i think. even at that imagine the diesel would have better overtaking power.

    personally i never considered the 330/530d. the 530i/330i is quicker is 95% of situations, plus my dad has a 520d e60 auto and the noise of the diesel with an auto box really put me off. added to that most used diesels are high milers for obvious reasons (ie person who bought them probably bought them to do higher miles)


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    prospect wrote:
    Off the mark, it is purely for high testoterone, low brain level, tennage childishness.

    In the mid range, when safe overtaking is the issue, 9 out of 10 Turbo Diesels will easily out perform a similarly sized petrol engine.

    such a broad sweeping statement, if its std boring rep mobiles like a std mondeo etc yes the 1.8 diesel is normally better in the mid range than the 2.0 petrol or whatever.

    if its performance cars then that argument doesnt stack up.

    In most cases the 2.0 golf gti is quicker than the 2.0 golf gt, bmw 530i is quicker than the 530d, plenty of other examples


  • Closed Accounts Posts: 118 ✭✭nastysimon


    prospect wrote:
    They were both standard road going versions, driven by the same driver, me. Almost everyone that drove them had the same opinion, and their times also confirmed, the diesel was FAR quicker. Stop trying to pick fault where none exists..
    How much quicker is "FAR quicker"? Sorry, I just don't believe that the diesel was "FAR quicker" when driven by a driver who was willing to drive both at their limits. If I experienced it, I might change my tune, but your claim is against all of my experience of diesels and everything that I have read by experts.
    So by this statement you mean that your OPINION is better, or more qualified than mine!! What an arrogant person you are.
    Not at all, just that mine has the weight of experts behind it, yours doesn't seem to. I tend to trust experts until I'm given very good reason to believe that they are wrong. It tends to be the safest course of action. One might say that going against the experts without very solid proof to back you up is much more arrogant, though I will still refrain from calling you such. Please keep the personal insults out of it.
    I don't need figures to back up my opinion. You have obviously no interest in what others think, and I can see you are the type of person who always considers themself right.
    Also my argument is not about speed (read the posts), it is about how the engine is more suitable for driving in everyday situations. Maybe you consider accelerating away from the lights and 'beating' a family in a diesel MPV who have no interest in 'racing' you to qualify you as a "petrol head". I consider that selfish and irresponsible.
    The section to which you are responding wasn't directed at you, but galwaytt. I always consider myself correct until I have good reason to believe otherwise (don't we all), especially when I have good experience of the area. I tend to trust experts over non-experts and trust their experience until I have significant experience of an area myself. My experience backs up my opinion. Yours may well back up your own, but it still doesn't convince me. I never every suggested that I ever engaged in traffic light racing, so why do you feel the need to personally attack me over it. As it is, I like to be quick away at the lights, but I don't accelerate hard as there is no need. Being quick away means that more can get through. You really are making huge leaps from my suggesting that being able to accelerate hard is important.
    Off the mark, it is purely for high testoterone, low brain level, tennage childishness.

    In the mid range, when safe overtaking is the issue, 9 out of 10 Turbo Diesels will easily out perform a similarly sized petrol engine.
    I never said that one should do so off the line, I just pointed out that having the ability to do so is safer than not. Believe me, having a 0-60 time of 5 seconds has its perks over a 0-60 of 10, even from safety points of view. When cruising and going to overtake, you should complete the move as quickly as possible, so staying in 5th gear is not the best solution, for diesel or petrol. Since it takes as long to drop two gears as one, you are better off in the petrol, which can be made to pass faster.

    Now, I'm not happy with the way this thread is moving. Personal insults aren't needed. I accept that for you a diesel is a better choice, but I will not accept that one would pick a diesel over a petrol for the purer driving experience. There is nothing that you can say that will change that opinion, though if you could point me at an article by an expert, that might change it. Similarly, a good sports car with a diesel engine might too.


  • Registered Users, Registered Users 2 Posts: 21,263 ✭✭✭✭Eoin


    nastysimon wrote:
    There is nothing that you can say that will change that opinion, though if you could point me at an article by an expert, that might change it. Similarly, a good sports car with a diesel engine might too.

    None of the ones I mentioned earlier would do?

    BMW 335d, Alfa GT & Brera. BMW 535d may not be a "sports car" as such, but a colleague of mine coming from a petrol coupe drove one, and found the twin turbo makes for a seriously quick ride. I don't know what the merc coupes are like, but they come with diesel engines.


  • Registered Users, Registered Users 2 Posts: 20,470 ✭✭✭✭Cyrus


    its a matter of preference i spose, if i was looking at a 335, id go for the i not the d


  • Closed Accounts Posts: 118 ✭✭nastysimon


    eoin_s wrote:
    None of the ones I mentioned earlier would do?

    BMW 335d, Alfa GT & Brera. BMW 535d may not be a "sports car" as such, but a colleague of mine coming from a petrol coupe drove one, and found the twin turbo makes for a seriously quick ride. I don't know what the merc coupes are like, but they come with diesel engines.

    None of these are even close to being a sports car. You'll also note that the top of the line for each of those cars is petrol engined. A bit odd that ;)


  • Registered Users, Registered Users 2 Posts: 2,991 ✭✭✭el tel


    I drive mostly on motorways and I find the main benefit of a diesel over petrol (aside from less frequent trips to the pumps) is the lower revs at M-way cruising speeds. I simply couldn't stand being in an average sized petrol car for long perods at anything much over 60mph.

    However, in city driving I found that in my diesel I had to stir the box much more than I do in my other (petrol) car which I believe is down to the the much narrower power band of the diesel engine. For this reason I much prefer the petrol for urban driving.


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