Mercedes Top Luxury Car

[C43AMG]

I assumed you were talking about the horror of the diesel-engine idle sound as you hand the keys to a valet outside a posh hotel. Imagine the disgrace!

Absolutely Shude. And the same to you Fuzzer

 

[MBManInKen]

Or the horror faced every month when the fuel bill comes in for the petrol models
Ill take the diesel idle any day

I would hope that no petrol owner would want to disagree with that. Diesels provide the better economic case.

Personally, I am prepared to bear the higher costs of driving my V8 petrol and I am not losing any sleep over it, it just gives me driving enjoyment and refinement that no diesel has been able to give me, but I do accept that it comes at a price!

 

[Dieselman]

Absolutely Shude. And the same to you Fuzzer

In this case why not just go for a 280/320 as they sound nicer than the petrols and not gruff at all, just a deep burble.

 

[recycled]

Diesels do not always give better economy except if you are doing galactic miles. they cost way more to buy and service .diesel is more expensive at the pumps, at least in my garage and our focus tdci company cars has huge bills as well even though we do 30000miles a year.
The noise may be quieter but they have compression ratios of about 22:1 so that is still noiser.
It is basically up to choice. Some do like em some do not.
For me Until they make a diesel that sounds like a mossler mt900r V8 i would never want one.
And when ferrari and porsche start making diesels people might have a change of heart

 

[hawk20]

Diesels do not always give better economy except if you are doing galactic miles. they cost way more to buy and service .diesel is more expensive at the pumps, at least in my garage and our focus tdci company cars has huge bills as well even though we do 30000miles a year.
The noise may be quieter but they have compression ratios of about 22:1 so that is still noiser.
It is basically up to choice. Some do like em some do not.
For me Until they make a diesel that sounds like a mossler mt900r V8 i would never want one.
And when ferrari and porsche start making diesels people might have a change of heart

You are clearly somewhat out of date. Check the MB website and you will see many diesels are now no dearer than equivalent petrols. Also check the E class figures and you will see a 3 litre diesel giving as much performance as a 3.5 litre petrol engine.

As for Ferrari and Porsche having lost Le Mans to a diesel car, perhaps they too may start to see sense.

And by the way when the petrol S classes start soon to pay £25 per day in London for the congestion charge ,while the diesels pay the normal amount, I think we can expect to see a lot more converts. At the moment only a modest 60% of S class owners choose the diesel.

Big petrols will soon be like dinosaurs except for those who can make shareholders or taxpayers, or both, pay their bills. Sad for some, no doubt, but I think that is where we are going.

 

[Mactech]

It's horses for courses...

My road car is a diesel.
My wifes open car is petrol
The van is diesel
The bike is petrol

This years Le Mans car is err...petrol.
Last years world landspeed record car was...diesel!

Still think the best car on the road is a S320 CDI and might soon be an owner.

 

[recycled]

You are clearly somewhat out of date. Check the MB website and you will see many diesels are now no dearer than equivalent petrols. Also check the E class figures and you will see a 3 litre diesel giving as much performance as a 3.5 litre petrol engine.

As for Ferrari and Porsche having lost Le Mans to a diesel car, perhaps they too may start to see sense.

And by the way when the petrol S classes start soon to pay £25 per day in London for the congestion charge ,while the diesels pay the normal amount, I think we can expect to see a lot more converts. At the moment only a modest 60% of S class owners choose the diesel.

Big petrols will soon be like dinosaurs except for those who can make shareholders or taxpayers, or both, pay their bills. Sad for some, no doubt, but I think that is where we are going.

I am not out of date at all. Diesels are more expensive to buy and service period.about £500-1000 more which is a lot if you are on HP or PCP .

The only time a diesel car on whatever make and model can match an equivalent petrol in performance is only cos they have one and sometimes two massive turbos stuck to them. if you get an e280 cdi without a turbo you will be doing 0-60 in light years .If you stick a turbo in a e280 you will leave the diesel for dead.

The kind of diesel used in Le mans is not the kind you buy from the pumps whereas the gasoline used is very identical to petrol
Furthermore audi won at le mans with a diesel car cos they have different rules to accommodate diesel engine weight. e.g 5.5litres for diesel turbo with very high boost and only 4 litres for petrol turbo with restricted boost or 6 litres for normal aspirated petrol
Not a level playing field then as the petrol are disadvantaged.

Porsche is still the most succesive car at le mans and if they all were allowed to have the same engine size and the same turbo, the diesel audi would not stand a chance.

A lot more restrictions go into the petrol models that i can not go into here cos officials deemed their top speed unsafe as they were generating 1500hp in qualifying trim with turbos.
Remember turbo bans in F1 cos of brabham BMW engine?

Sauber c9 mercedes did 247mph on the mulsannes straight and so chicanes were then introduced.

The reason most people choose diesels is not always because they like them.Sometimes it is because economy and company car policies dictates so. If a ferrari cost £200, no one would buy a fiat punto anymore.
So the reason there are more puntos than ferraris is not cos people prefer puntos mate. It is because that is what the economy of their wallet dictates.

 

[MBManInKen]

f a ferrari cost £200, no one would buy a fiat punto anymore.

I certainly don't want a punto, but I wouldn't buy a Ferrari if it was the last car on the planet, irrespective of price.

As John so often says: each to their own. I think we're all allowed our own tastes and preferences, not?

 

[recycled]

if you read my initial post , that is exactly what i said. some like it and some do not. what i do not want is people trying to convince me that what i do not want ,which is a diesel car is better than what i want, which is a petrol car.

 

[Will]

I like a lot of aspects of modern diesels, in fact I probably drive more miles a year in Diesel cars than my own petrol cars.

I do however agree with some of the points raised here, in that it seems as to promote the modern diesel over the years they have been putting a large amount of R&D into them and have tried to market them as firstly being nearly as powerful as the petrol equivelent, then 'as powerful' and on occasions 'more powerful' although I'm sure with the same level field of turbos and states of tune etc the petrol engine would nearly always be better in this respect?

There's no point trying to deny the fact that even the very best diesel engines (as might be offered in an S-class Mercedes) are still a slight amount away from being as smooth, quiet and powerful as the best petrol engine on offer. A lot better than they used to be, and certainly the obvious choice environmentally or economically, but maybe just that step behind the best petrol engine on offer

I'm 50/50 personally

Oh and three more -ves of diesels from the top of my head:

They often give puffs of smoke out the back when being 'opened up'
Diesel pumps are normally greasy and smell
The idling sound (especially from cold) is always noisier than the petrol equivelent


Will

 

[Dieselman]

I wasn't going to join in with this thread but Recycled I have to say that your posts clearly indicate that you are well out of touch with modern engines.
I know you say you drive a Focus diesel and it costs a lot to maintain, well that's an unreliable Ford for you.

You somehow make the age old connection between cubic capacity and relevence between petrol and diesel. I used to hear this from people who caimed to know 15 years ago, it is unscientific and out of date reasoning. Why? Because power output is created by fuel burned not cubic capacity, and diesels burn significantly less even when in Le-Mans trim, and even though they are turbocharged to a higher level.
Remember a petrol turbo will drink even more fuel as it then requires waste fuel to stop pre-ignition and to cool the cylinders due to the lack of thermal efficiency.

This is why the different rules are in force for the different engine types at Le-Mans.

Anyway it's irrelevant to talk about relative power outputs as power is a meaningless figure and the engine doesn't actually generate power at all. The engine generates torque from which theoretical power is calculated. Power is simply an exponent of engine revs so the higher an engine revs the more power it will generate, whereas torque is a real figure of actual force.

Anyway power only gives top speed whereas torque gives accelleration, hence the diesels outperformed the petrols leading out of every corner.

It's not only the petrol engines are limited in output the diesels are as well, not only in Le-Mans but other multi fuel series as well.

If you took the power output of the petrol engines at say 4500rpm it would be similar or less than that of the diesel at the same revs because the diesel will generate more torque due to higher thermal efficiency.

The only bit you get close to is the higher compression ratio, but you will find that is now in the region of 18.5:1, not the 22:1 it used to be.

It isn't the compression that causes the diesel noise at idle, it's the rapid rate of cylinder temperature rise mainly due to the engine operating seriously over lean. This noise goes once the engine is put under load as the mixture is no longer so lean.

A few years ago we ran a RR shootout day and it was noticed that the quietest engines when on the rollers were the diesels....

As far as purchase price and servicing are concerned, MB diesels are the same price as petrols but residuals are much better and servicing can be cheaper due to the cars going longer between oil changes or needing spark plugs.


Rant over.

 

[MBManInKen]

What I am personally most amazed about is how this question of diesel versus petrol resembles almost religious wars. Each side seems to feel compelled to go to almost absurd lengths to represent their choice (for diesel or petrol) as the "best".

In the end, different people have different requirements, cover differing mileages, have different preferences.

Mercedes and other brands therefore offer different engine options to serve the different segments of the market.

Should that not be the end of it? I find it slightly silly to see how everyone claims ownership of absolute truths in this debate. Especially, since the "right" answer is by definition different for different people.

And whether or not a petrol or a diesel engine comes first in an event or not, frankly, I could not give a monkey's about. It certainly does not change the above notion that different people will, for whatever reason(s), end up chosing different vehicles. It's a free country after all.

I do find it a bit worrying when people want to dictate other what they should or should not choose to do...

 

[Dieselman]

What I am personally most amazed about is how this question of diesel versus petrol resembles almost religious wars. Each side seems to feel compelled to go to almost absurd lengths to represent their choice (for diesel or petrol) as the "best".

I do find it a bit worrying when people want to dictate other what they should or should not choose to do...

I don't recall doing either of these, simply correcting innaccuracies.

Please correct me if I am wrong.

 

[MBManInKen]

I don't recall doing either of these, simply correcting innaccuracies.

Please correct me if I am wrong.

Hey, I wasn't replying to you! Sorry if I gave the impression I reacted to your post, my comment was a general one looking at this thread.

 

[Dieselman]

Oops, I guess it's just that your post came in just after mine...

I personally don't care what cars people chose to drive and do agree that diesel engines transmit more noise to the cabin, however some of the so called facts of the merits or demerits of each type are inaccurate and should be addressed.

Regards

 

[Mactech]

In a world where tyre noise is more intrusive than engine noise, and it costs more to re-fuel than to buy a colour TV (imagine that 25years ago!), Mercedes engineering still makes the S320 the 'best' luxury car at the moment. In short, I agree with What Car? Isn't that where we came in?
I won't try to define 'best' but I think I am about to buy one!

 

[MBManInKen]

some of the so called facts of the merits or demerits of each type are inaccurate and should be addressed.

I couldn't agree more!

 

[recycled]

Diesel man .I am not going to rant. We are all adults here you are very knowledgeable in engines so I commend you. I must say I read your post with amazement as it shows that you have not come to grasp with modern engine research and development and have a certain bias tending towards diesels hence the name.
I have always said it is a debate and a matter of choice depending on your needs and requirements.
An engine produces power and torque. Power in an engine
Q=mcp (T-t) x revs per minute
M= mass of air in combustion chamber
Cp=specific heat capacity of fuel used
T-t = Temperature before and after combustion
Q =energy produced in joules x r.p.m where m is converted to seconds = wattage engine power in watts
1 hp = 746 watts
An energy produces torque as well or pulling power as it is called in the industry .Nm = work done or energy transferred through a distance.
Relation between power and torque goes through time applied.
Power = workdone;energy transferred; torque/ time taken
Any engine can be tuned for maximum torque or max power depending on what it is used for.
The diesel develops more torque easily because it has a higher specific heat capacity and greater density that is why most are used in trucks.
But the petrol would always produce more power albeit at higher revs as it is directly proportional to r.p.m
As of today I do not know of any engine and correct me if I am wrong that given same conditions and capacity that a diesel would outperform a petrol. If we lose all forced induction the diesel would struggle.
You say power is created by fuel burned not cc. Agreed. But I say the bigger the cc the more fuel you burn. Easily. Now you can compensate by forced induction which is still the same because you force more air in at higher pressures and I rather we lose all forced induction.
As far as I know the 530d or is it 535d has two turbos.
We did have a Peugeot 306 XD without a turbo and I can not even begin to tell you about the performance. Until we changed it to a D-turbo.
And just to correct you, I do not drive a focus diesel it is part of the company fleet(would not drive one if i was paid to do it) and I just get driven in it.
Acceleration is change in velocity over time and unless the diesels have turbos strapped on them, they will never outperform any petrol car of the same spec out of any corner.

 

[Dieselman]

I actually agree with most of what you have said but would still say that you need to be careful about the fuel being injected as as you rightly point out, this provides the calorific energy.

A diesel of even greater capacity will use less fuel to make the same torque output. this is as a result of the thermal efficiency rather than the engine tuning.
Diesel engines typically have thermal efficiencies of 45-50% whereas the best petrol engines are 25%.
Low power diesels really are miserly in their consumption of fuel so aren't really a fair comparison.
It would be better to refer to power output agains specific consumption as opposed to cubic capacity.

The issue about power is that a petrol engine will always generate more power due to the ability to rev above 5252rpm, whereas most diesels cant. However power is only used to combat air resistance, whereas torque, which is actually measured as opposed to being calculated, is used to accellerate the vehicle mass, including dragging it up hills.

The real point of my original post was to say don't use older diesel technology as a guideline because the playing field has moved a long way due to direct injection and injection systems.

Anyway. As you said we are all adults so sorry if for any offence..

 

[recycled]

I actually agree with most of what you have said but would still say that you need to be careful about the fuel being injected as as you rightly point out, this provides the calorific energy.

A diesel of even greater capacity will use less fuel to make the same torque output. this is as a result of the thermal efficiency rather than the engine tuning.
Diesel engines typically have thermal efficiencies of 45-50% whereas the best petrol engines are 25%.
Low power diesels really are miserly in their consumption of fuel so aren't really a fair comparison.
It would be better to refer to power output agains specific consumption as opposed to cubic capacity.

The issue about power is that a petrol engine will always generate more power due to the ability to rev above 5252rpm, whereas most diesels cant. However power is only used to combat air resistance, whereas torque, which is actually measured as opposed to being calculated, is used to accellerate the vehicle mass, including dragging it up hills.

The real point of my original post was to say don't use older diesel technology as a guideline because the playing field has moved a long way due to direct injection and injection systems.

Anyway. As you said we are all adults so sorry if for any offence..

I totally agree with you anyway .
have a nice weekend and no offence intended in any way.