Are Diesels Worth It Anymore

JHMEG

biggus wrote: »

Guys there developed pulse and glide driving techniques and some are approaching 100mpg unmodified.

Was actually some Japanese guys that developed P&G and they're able to get close to 120mpg.

Something else that came to my attention recently which is growing in popularity in the US is what they call Hypermiling. This site has some excellent articles, including getting 103mpg from a Diesel Civic by hypermiling.

http://www.cleanmpg.com/cmps_index.php

Cyrus

biggus wrote: »

Used an 04 prius for a while and the best i got Dub to wexford was 73mpg for the 80 miles (not instantaneous) this was during N11 roadworks.
Normally 48 mpg around town and 55 on long journeys without trying.
Was the better halfs car so any attempts by me to go for really good MPG were undone when I wasn't driving.
See http://priuschat.com/forums/ see how these yolks have turned america upside down. Guys there developed pulse and glide driving techniques and some are approaching 100mpg unmodified.
Don't knock a prius til you try one. Quite quick too and automatic to boot.

those guys are a danger on the road from what ive seen

and a prius is quick, cmon

the prius has to be the biggest scam yet, hybrid that pollutes so much in the making as to make it a bigger polluter than most other cars and an ED bmw 520d is a more efficent, nicer looking, better driving, better everything car

Stevie Dakota

I am sure that increasing diesel prices will erode some of the appeal, but diesel is NOT just about economy. The performance is so much more usable due to the higher torque, combined with relaxed cruising and good economy for me it is a win win.

E92

The performance of diesels is great... until you hit about 3-3,500 rpm and then they lose the will to live and perform.

They give people the mistaken impression that they are faster than petrols, when in fact they're not, and if you really push them you'll find that they've nothing to give, while a petrol has plenty of performance to offer if you take them into the upper half of the rev counter.

Most petrol engines in the future will be turbocharged, and will have all that torque at lovely low revs that all the dieselheads love, while direct injection petrol engines can make great strides on diesel economy, further eroding diesel's appeal.

Cyrus

Stevie Dakota wrote: »

I am sure that increasing diesel prices will erode some of the appeal, but diesel is NOT just about economy. The performance is so much more usable due to the higher torque, combined with relaxed cruising and good economy for me it is a win win.

they 'feel' faster

they arent faster tho

and how can the noise of a diesel = relaxed cruising?

With the price increases soon there will be no reasons left to drive a diesel.

They are noisey, smokey and boring to drive. Give me a good petrol engine anyday of the week.
You can take my 6 pot from my cold dead hands

Stevie Dakota

Cyrus wrote: »

they 'feel' faster

they arent faster tho

and how can the noise of a diesel = relaxed cruising?

Have you driven a modern diesel? The wifes Megane is whisper quite at 120kph loping along in 6th gear.

I would argue they are faster when it matters, overtaking, no need to change down, just foot down and off you go.

E92

ronoc wrote: »

You can't take my 6 pot from my cold dead hands

+1,000.

6 cylinder petrols ftw everyone:D! They're a world apart from boring old 4 cylinders, they have the smoothness, joie de vivre and noise that 4 cylinder engines just simply don't.

I never intend on going back to 4 cylinders, not if I can help it at the very least!

Cyrus

Stevie Dakota wrote: »

Have you driven a modern diesel? The wifes Megane is whisper quite at 120kph loping along in 6th gear.

I would argue they are faster when it matters, overtaking, no need to change down, just foot down and off you go.

yep my old man has a new 520d, id imagine its a more refined car than the megane? i hate it

craichoe

E92 wrote: »

This is Ireland not continental Europe and in Ireland we use mpg, like it or lump it.

I don't know what litres per 100 km are, besides which my cars are calibrated in shock horror miles and worse still:rolleyes: is that one of them has an instantaneous fuel consumption meter that measures my fuel consumption in.... miles per gallon(the M50TÜB20 engined E34). The other car has a trip computer and guess what it uses mpg too(B4184SM Volvo).

Even my old man's car which has a km/h speedo told me today it was averaging 35 MPG. Imagine, the "cheek" of a modern car with a km/h speedo to be able to display mpg:eek:! What is the world coming to:rolleyes:?

Most metric cars with trip computers can have their odometers and trip computers switched over to miles at the touch of a button, so I don't see what is so bad about continuing to use miles, apart from the fact that the PC brigade want us to do so and to make us "look good" in front of our European neighbours?

If we really want to impress our European neighbours how about we try and make some effort to learn one of the languages they speak rather than PC symbolic gestures, you'd never know they might just appreciate our efforts to try and speak their language:rolleyes:.

OT but ..

We did.. its called English .. pity we lost our own language though.

And the french don't speak German or Dutch, the belgians speak french and dutch as an example. But the universal language for business is .. sad to say .. English.

vectra

E92 wrote: »

Most petrol engines in the future will be turbocharged, and will have all that torque at lovely low revs that all the dieselheads love, while direct injection petrol engines can make great strides on diesel economy, further eroding diesel's appeal.

So,
You are saying that a 1.4 TSI SEAT Leon Petrol would be as economical or near as economical as my SEAT Cordoba 1.4 tdi S when I do most of my driving in short journeys ?:rolleyes:

Zube

Stevie Dakota wrote: »

I would argue they are faster when it matters, overtaking, no need to change down, just foot down and off you go.

It's a question of driving style. Some years ago we changed from a 150 bhp Alfa 16V to a 115 bhp diesel. The wife didn't really find the diesel slower, because at low revs the diesel had more torque, and that suits her driving style.

I noticed a big difference, since I would wring the Alfa's neck up around 6-7000 rpm, and that's where the power was.

Marcus.Aurelius

I could never go back to diesel. I bought a Lexus GS300, and couldn't be happier. 6 cylinder in-line. (I6). Smooth as silk, no vibrations. Straight sixes are the optimum design for perfect balance.

see http://en.wikipedia.org/wiki/I6

Smoother than V6, and longer life too!

vectra

Zube wrote: »

I noticed a big difference, since I would wring the Alfa's neck up around 6-7000 rpm, and that's where the power was.

Yes,
We would all have noticed the difference when we were young and careless where Speed limits were something that never entered our heads. Same as other road users were non existant and didnt matter if we killed or maimed a few of them on our way.:o

Exactly what speed would you be doing at 6 ~ 7K revs
OH
And what would the consumption be like on the Alfa Petrol Guzzler at that limit :rolleyes:

Stevie Dakota

This is pointless, the whole petrol V diesel thing, they are different animals. At home we have a Renault 1.5 diesel 4 pot and 2 litre straight six BMW, they are both fantastic engines, yet totally different in their power delivery. The BMW loves being revved and is as smooth as silk, but the Renault is more relaxed when hustled, no need to drop two gears and redline it to make swift progress.

We always have a dilemma when driving cross country, the BMW is more comfy, but the Renault is thoroughly effortless, fast and economical with it.

JHMEG

maoleary wrote: »

I could never go back to diesel. I bought a Lexus GS300, and couldn't be happier. 6 cylinder in-line. (I6). Smooth as silk, no vibrations. Straight sixes are the optimum design for perfect balance.

see http://en.wikipedia.org/wiki/I6

Smoother than V6, and longer life too!

That is all true. I6 is perfectly balanced.

However balance is not what I look for, at all, ever. There are sooo many more important things in an engine.

quarryman

ronoc wrote: »

You can take my 6 pot from my cold dead hands

+ 1000000

Zube

vectra wrote: »

Exactly what speed would you be doing at 6 ~ 7K revs

Peak power was at 6400 rpm which was about 90 mph in 3rd, if I recall correctly. The tachometer was shaded red from 6000 to the redline at 8000, and the manual said "Do not drive for long periods with the needle in this zone".

And what would the consumption be like on the Alfa Petrol Guzzler at that limit :rolleyes:

It used to average mpg in the low 30s, so probably 25 with me driving. Fuel was a minor cost compared to depreciation on that machine.

Biro

Stevie Dakota wrote: »

2 litre straight six BMW, .

Do you mean a 2.2? What age is the beemer?

Stevie Dakota

Biro wrote: »

Do you mean a 2.2? What age is the beemer?

Nope 2.0, last of the E34's.

Marcus.Aurelius

JHMEG wrote: »

That is all true. I6 is perfectly balanced.

However balance is not what I look for, at all, ever. There are sooo many more important things in an engine.

Oh sorry, its 228 bhp is that better?

E92

vectra wrote: »

So,
You are saying that a 1.4 TSI SEAT Leon Petrol would be as economical or near as economical as my SEAT Cordoba 1.4 tdi S when I do most of my driving in short journeys ?:rolleyes:

No I'm saying that a direct injection petrol can be considerably more efficient than a conventional petrol, which therefore erodes some of the economy advantage of diesel over petrol. Besides which it's hardly fair to compare a Leon with a Cordoba.

Direct injection petrols are particularly efficient if you ease up on the throttle.

I know all of this because I have a direct injection petrol Volvo S40 that will do 55-60 mpg(as well as an E34 520i) on the open road if I stick to the speed limit and drive it gently. Officially it does 50 mpg in out of town driving, but if you're careful and watch the mpg meter you can get plenty more from it.

My old man has a 1.8 Avensis and if you drive it in similar circumstances you get around 45-49 mpg, maybe you'll get just above 50 if you're really careful. Officially the Volvo does 40.9 mpg and the Toyota does 39.2.

As direct injection engines go, the Volvo's is a very old fashioned system(since it is actually the infamous GDI system no longer used by Mitsubishi), being less smooth than a conventional 4 pot, it sounds like a diesel on start up, especially when it's cold, it's noisier than a conventional petrol engine and has a complete intolerance of low quality petrol, which causes excess build ups of carbon in things like the throttle body, which then makes it stick a little due to excess carbon from poor quality petrol, so it can cause a delay between the time you put your foot down and the engine responding. It was very advanced techology when it first came out in 1996 though.

But just as with diesels, the technology has improved considerably since then, and modern direct injection petrols are no louder than conventional petrols, even when they're cold. I'm sure they have long sorted the fuel issues with direct injection petrols and anyway the sulphur content has come way down in petrol as it has with diesel.

Then when performance is required, direct injection engines have a high performance mode which gives them greater performance over an old fashioned indirect injection petrol, so you have the best of both worlds.

alexmcred

E92 wrote: »

No I'm saying that a direct injection petrol can considerably more efficient than a conventional petrol, which therefore erodes some of the economy advantage of diesel over petrol. Besides which it's hardly fair to compare a Leon with a Cordoba.

Direct injection petrols are particularly efficient if you ease up on the throttle.

I know all of this because I have a direct injection petrol Volvo S40 that will do 55-60 mpg on the open road if I stick to the speed limit and drive it gently. Officially it does 50 mpg in out of town driving, but if you're careful and watch the mpg meter you can get plenty more from it.

My old man has a 1.8 Avensis and if you drive it in similar circumstances you get around 45-49 mpg, maybe you'll get just above 50 if you're really careful. Officially the Volvo does 40.9 mpg and the Toyota does 39.2.

As direct injection engines go, it is a very old fashioned system, being less smooth than a conventional 4 pot, it sounds like a diesel on start up, especially when it's cold, it's noisier than a conventional petrol engine and has a complete intolerance of low quality petrol, which causes excess build ups of carbon in things like the throttle body, which then makes it stick a little due to excess carbon from poor quality petrol, so it can cause a delay between the time you put your foot down and the engine responding.

But just as with diesels, the technology has improved considerably since then, and modern direct injection petrols are no louder than conventional petrols, even when they're cold. I'm sure they have long sorted the fuel issues with direct injection petrols and anyway the sulphur content has come way down in petrol as it has with diesel.

Then when performance is required, direct injection engines have a high performance mode which gives them greater performance over an old fashioned indirect injection petrol, so you have the best of both worlds.

Have a new Golf 140bhp 1.4 TSI and the power it delivers accross the rev range is great. Was looking at a 1.9 TDI SEAT leon before it and the TSI is far better at power delivery. Also the road tax is a lot cheaper.

Zube

alexmcred wrote: »

Also the road tax is a lot cheaper.

Not for long.

E92

To be fair the best comparison is between the 1.4 TSI 122 bhp and the 1.9 TDI 105.

To show you the kind of progress direct injection petrols have made, just look at the comparisons between the 1.6 102 bhp Golf and the 1.4 TSI 122 bhp, particularly in the areas of economy and emissions.

E92

Oilrig wrote: »

Whats confusing about the Metric system?

At least you can use a calculator to solve it... try that with Ounces, Pounds & Stones...

The US have been trying to convert to Metric for 40 years...

...and still measures temperatures in degrees Fahrenheit.

The US doesn't know what the metric system is, watch any American programme on TV and it's always old fashioned meaurements they use.

The Americans still think guns are a good idea ffs!

JHMEG

E92 wrote: »

To show you the kind of progress direct injection petrols have made, just look at the comparisons between the 1.6 102 bhp Golf and the 1.4 TSI 122 bhp, particularly in the areas of economy and emissions.

A proper comparison would be between the 1.4 TSI 122bhp Golf and a 1.3 Turbo 130bhp Glanza. *Both* have turbos, one is a new design DI, the other is not.

maoleary wrote: »

Oh sorry, its 228 bhp is that better?

Only if it's meeting or exceeding 100bhp per litre. Or is twin turbo.:p

E92

Diesel sales in Europe are widely expected to fall after 2015 when new emissions standards come in to force that will only make diesels as clean as petrol were made clean in 2005: source.

Already Merc and BMW have decided to cancel their V8 diesels. They're not cancelling their V8, V10 or even V12 petrols though. Hmm. Has anyone noticed how quiet car makers have gone about diesels that are 50 state compliant in the US recently? That's because it turns out that the diesels that were supposed to be 50 state compliant in the US only meet this years standards. When the new Californian standards come in to place next year diesels will no longer be able to be sold in at least 5 and up to 12 of the 50 US states.

Contrary to popular belief, Europe's emission standards, especially for diesels are one of the easiest to pass in the developed world, and make a mockery of the claim by the EU that the EU is a world leader in environmental standards.

Of course all of this comes as we get ready to become the quickest country to go from petrol to diesel in the entire EU thanks to the new VRT rules, and diesels will, in the short to medium term at least, be the best choice for most people buying a new car after July. How ironic really.

The rising price of oil, especially diesel vis a vis petrol all over the world is starting to put the brakes on diesel sales already and 2007 may well have been the strongest year for diesel sales in Europe, confirming what I have long said about diesel: it's an expensive fad that we will grow out of. Petrol engines are getting more efficient(direct injection) and more powerful, as well as a lot more torquey(turbo/supercharging), so they are regaining the performance advantage they always had over diesel, and clawing back some of the economy advantage.

In the period Jan-April 08, diesel sales in Germany were 45.9%. In 2007 they were 47.7%(the best year for diesel sales in Germany, at one stage they nearly hit 50% there last year), so they have declined by 1.8%, and they'll start to fall even further across Europe as the price of diesel continues to rise.

Phaetonman

The performance of diesels is great... until you hit about 3-3,500 rpm and then they lose the will to live and perform

I was doing 90mph in my diesel yesterday and it was doing 2800rpm. You don't go past 3000rpm so no problem. Much quieter than an equivalent petrol taht would be pumping away at 4500rpm. Tdi power!

vectra

E92 wrote: »

Diesel sales in Europe are widely expected to fall after 2015 when new emissions standards come in to force that will only make diesels as clean as petrol were made clean in 2005:

Thats 7 years time..!! :eek:

if petrols are coming on that good then do you think Diesels are going to stay as they are now?
Look at the jump Diesels have made over the past few years.

All rubbish I say ..
I have had petrol cars all my life and they did nothing only drank petrol once the foot was pushed down and also around town.
Since i bought my TDi I will never go back to a petrol sucker.