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Discussion Starter #1 (Edited)
Petrol (vs) Diesel

EDIT: See post #3 for corrected peak torque figures, I got my wires crossed reading the online manual.


I currently have a loan diesel Giulia (single exhaust so this is a 150HP model, torque being the same as 180HP as per manual - 380Nm : 150HP @ 4250 rpm, 180HP @ 3750 rpm) as opposed to my own 2.0 200HP Petrol Super (200HP, 330Nm @ 1750 rpm) . So I thought it would be good to do a comparison of the two engines and post my thoughts.

NOTE: This post is no way intended as one engine is better than the other but purely an objective comparison slightly tainted with my subjective experiences and preferences.
My impressions of the diesel are over 2 days, roughly 100miles with about 30 miles of motorway, 60 miles of A roads and 10 miles of town, using mainly N and D modes with the occasional A mode for testing purposes. As I know the Giulia already very well, I was able to zone in on the engine alone and filter out the infotainment, drive and handling aspects which are pretty much embedded in my sub-conscious.

STARTING/TAKE OFF: Diesel as expected sounds a bit clattery from cold start. On moving off with the engine cold, it continues to be a bit gruff until normal operating temperature is reached when it quietens down a lot. Strangely, the engine sounds quieter/more refined from outside than from inside the cabin at cold starts and initial take off, until engine warms up. This I find is a lot quieter and pokier than the C-class Diesel I drove a while ago which sounded like a tractor. The petrol in comparison is understandably quiet at start-up and take off, although the petrol Multi Air engine I find is a bit noisier/rougher than the 2.2JTS engine I owned before which was smooth as butter.

CRUISING/OVERTAKING: In steady cruising speeds, the engine is fairly refined and quiet and it is not easy to distinguish between the diesel and petrol. There is no diesel drone, with perhaps a slightly louder engine note that will give away it’s a diesel if you really pay attention, more so with stereo off. If throttle input is given from cruising speed, the engine note changes and it lets you know it’s a diesel, however it remains fairly refined. Power delivery is smooth and progressive similar to the petrol. There is more torque than the petrol obviously which shows in how strongly the diesel pulls, but with my petrol the peak torque comes is below 2000rpm where as in the 150hp diesel it comes in at 4250 rpm so the engine likes being revv’d a bit more than the petrol to do the same sporty overtaking/speed increase manoeuvres. Gearbox is the same and changes are smooth and progressive.

Drive modes: A is really sluggish, more so than the petrol. N is fine for day to use and normal driving. D is very responsive and quite fast, almost sporty (“almost” when compared to petrol). In D, the engine revs higher and harder and the note becomes a bit louder, but you always still know you are driving a diesel. And on that count, for the sake of sportiness I prefer the petrol which especially in D mode is proper sporty and rapid if you are prepared to say goodbye to fuel. I find the way power is delivered in the petrol and how the engine note sounds with sporty driving in N and D a lot more “engaging and emotional” when compared to the Diesel. The 150HP is actually pretty rapid in D mode surprisingly and quite easy to get to high speeds, the 180HP will certainly feel more quicker.
In terms of fuel economy, I don’t think there is a huge difference between the modes if driving steadily, maybe about 4 to 6mpg at the most. In the petrol though you can have as much as 10+mpg difference between A and D.

START/STOP EVO – Although I am not a big fan of SS, I tried it. SS is a lot more refined and tad faster on the petrol. With the diesel, it’s a bit laggy and starts/stops with a bit of an unrefined jolt (in comparison). For this reason I personally would never leave this function active on the diesel whereas I might occasionally on the petrol.

OTHER OBSERVATIONS:
The wind noise from around the doors/seals I feel with my petrol is definitely present in the loan car as well. I think the problem is either due to excessive door panel gap or inadequate compression of the door seals, which leads me to think it’s a design shortcoming. Wind noise from both cars is far more noticeable than my previous 159. If others including some Qf owners have not noticed this then either they have different door panel gaps, different door seals or else they are subjectively not feeling/hearing it. The noise is not too intrusive though but it is there.
The passenger seat (super model) has the same wobble/damped vibration on rough surfaces and cruising speeds when unoccupied. I have come to the conclusion, this is caused by the lightweight and slim seat design and the way it has been mounted. The back support part does not appear to be stiff enough and wobbles from seat base to the top. Another design issue IMO. Again not a major issue as passenger seat is usually occupied by my son or my bag. Solution is get Veloce or Speciale seats and of course Qf seats (haven’t heard any issues with these so far).

OVERALL IMPRESSION:
Even in the 150HP guise, the engine is surprisingly refined once warmed up compared to cars in the same class (MB, BMW) , only the Audi diesel I feel is more refined (and more boring). Drive, gear box and handling is exactly the same on both engines. In the 180HP guise, it will be a tad bit more quicker as the identical torque comes in a little earlier. With the same impressive handling and slick gearbox, I prefer driving the diesel in D mode majority of the time especially given fuel economy is still high 30’s or early 40’s.

Now, the big question: Would I swap the petrol for the diesel? SHORT ANSWER IS NO. Being a long term petrol head and doing less than 10k miles a year, I prefer the refinement of the petrol engine and the way the petrol delivers the power while feeling more sporty when demanded, at the cost of fuel economy which is the only down side. Having said that, this is probably the first diesel I have enjoyed driving and may end up buying when coupled with how the Giulia steers and handles, especially in the Speciale trim. The fuel economy despite rapid driving is very impressive too. Both cars are equally good and serve specific requirements and therefore quite subjective, even if this sounds a tad non-controversial! :rambo:
 

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Hey @metalgod23

Quite a comprehensive comparison. Makes me wonder what 210hp diesel would do.

With regards to the section on torque, did you by mistake swap the observation? In my experience diesels pick up torque sooner but also drop sooner. This is also confirmed by bench observations:
150pk diesel: https://www.squadra-tuning.nl/content/uploads/Giulia-150-180pk-tuning-768x1175.gif
200pk petrol https://www.squadra-tuning.nl/content/uploads/Giulia-200-280-pk-belofte-werkelijkheid-768x652.gif

Cheers
 

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Discussion Starter #3
Whoops! Sorry. You are right, thanks for the correction. I quoted the figures from an older version of Owners manual found online and I mixed up rpm figures for HP with Torque.

I just checked my printed owners manual and it is:

Manual transmission is 380 Nm @ 1500 rpm for both 150hp and 180hp.

Automatic transmission is a massive 450 Nm @ 1750 rpm I.e. Same engine speed as petrol, which explains the low down poke in the diesel. 150hp peak is @ 4250rpm and 180hp peak @ 3750rpm as per manual.

Squadra graph is dyno based and what the car really delivers.

After posting, on my drive back this evening, I observed more closely and the diesel feels more like the corrected figures. It still likes to rev though which is why I got a bit confused and read the tech data in the manual incorrectly.
That's my excuse anyway :nuts:
 

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"Another design issue IMO. Again not a major issue as passenger seat is usually occupied by my son or my bag. Solution is get Veloce or Speciale seats and of course Qf seats (haven’t heard any issues with these so far)."

The electric Lusso pack passenger seat doesnt wobble either, so another option.
 

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Thanks MG, excellent report, with your usual high standards maintained. Without driving a 2.0 litre, from its spec and your observations, I know I'd love driving one. Diesel is currently 10 cent a litre less here then petrol, 1.25 vs 1.35, and has been for some time, which together with a 45 average and 190 a year road tax versus 280, makes it a economic no brainer, especially factoring in re-sale. We love our tractors here on the emerald isle.:wink_org:
 

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What about this for a comparison, with the current bad press and planned toxicity charges on diesel vehicles, in a couple of years no-one will touch them with a barge pole.
I spent a considerable amount of money on a diesel vehicle last year and now really wish I hadn't.
 

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What about this for a comparison, with the current bad press and planned toxicity charges on diesel vehicles, in a couple of years no-one will touch them with a barge pole.
I spent a considerable amount of money on a diesel vehicle last year and now really wish I hadn't.
Off topic I know but this was a big reason for me picking a 335i over a 335d X drive last year when I switched over to the dark side.
 

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I contemplated the petrol over the diesel
I did the same with a previous BMW and regretted getting the petrol
It hurt every time you visited the pumps
I m pleased with my diesel the economy is better than my previous vw golf blue mention and feels more refined, it's a personal thing on what you need from a car in a perfect world the QV would be the one for me
 

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The whole 'diesel is dead and will be wiped off the planet overnight' thing is complete rubbish. Domestic heating systems and older (pre-emission control) diesel cars, vans, buses, trucks and even trains, create the bulk of nox emissions. To wipe out diesel values would expose dealers and manufacturers to huge losses on the pcp values they are committed to. Won't ever happen. What you will see is further tech from manufacturers on reducing nox, and a gradual reduction in older diesels through natural wastage and incentives, i.e. scrappage schemes. Diesel is far from dead, its only getting started.
 

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The whole 'diesel is dead and will be wiped off the planet overnight' thing is complete rubbish. Domestic heating systems and older (pre-emission control) diesel cars, vans, buses, trucks and even trains, create the bulk of nox emissions. To wipe out diesel values would expose dealers and manufacturers to huge losses on the pcp values they are committed to. Won't ever happen. What you will see is further tech from manufacturers on reducing nox, and a gradual reduction in older diesels through natural wastage and incentives, i.e. scrappage schemes. Diesel is far from dead, its only getting started.
I presume you are talking purely from the perspective of opinion in the Republic of Ireland.

The comments on the future of diesel in this thread are taken in the context of the UK. Here the pressure is really on to do something about diesel emissions, the focus of this being in the big cities. Nothing firm has been decided yet but announcements on diesel emissions and local/national taxation will be announced after the UK General Election on 8th June. So in the UK the topic of diesel driven cars is a big issue.

No disrespect to the Republic but I doubt whether you have the same attention on diesels. Your only major city in the republic is Dublin, and that is a mere pimple compared to the major cities of London, Birmingham, Leeds, and Manchester in England. The population of the Republic is only 3 million, the UK 65 million. This explains in part the emphasis on the future of diesel in the UK, and any remarks you make in this respect within the context of the Republic are just totally irrelevant.
 

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I presume you are talking purely from the perspective of opinion in the Republic of Ireland.

The comments on the future of diesel in this thread are taken in the context of the UK. Here the pressure is really on to do something about diesel emissions, the focus of this being in the big cities. Nothing firm has been decided yet but announcements on diesel emissions and local/national taxation will be announced after the UK General Election on 8th June. So in the UK the topic of diesel driven cars is a big issue.

No disrespect to the Republic but I doubt whether you have the same attention on diesels. Your only major city in the republic is Dublin, and that is a mere pimple compared to the major cities of London, Birmingham, Leeds, and Manchester in England. The population of the Republic is only 3 million, the UK 65 million. This explains in part the emphasis on the future of diesel in the UK, and any remarks you make in this respect within the context of the Republic are just totally irrelevant.
and you are taking your opinion based on, the sun the mirror the telegraph reports of what might and might not happen! i'm still laughing at how many idiots thought the NHS might get some of the so called 350 million pounds we were going to get back! Frankly the reporting has been atrocious,full of half truths missing most of the facts indeed childlike and actually has me thinking what happened to proper journalism? If If this government of ours[,well i was going to say is stupid enough ,but heck they are stupid enough] to take serious action against ALL diesels it will backfire big time and could lead to petrol engines also coming under the same spotlight. after all the few test half heartily done on some petrol engines have shown their
NOX short comings too and besides the technology is there to help diesels.. on a plus note a huge fall in diesel sales over the next few years could actually bring the price of diesel down and the price of petrol up after all wasn't the rise of diesel sales the reason its price shot up..
 

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I presume you are talking purely from the perspective of opinion in the Republic of Ireland.

The comments on the future of diesel in this thread are taken in the context of the UK. Here the pressure is really on to do something about diesel emissions, the focus of this being in the big cities. Nothing firm has been decided yet but announcements on diesel emissions and local/national taxation will be announced after the UK General Election on 8th June. So in the UK the topic of diesel driven cars is a big issue.

No disrespect to the Republic but I doubt whether you have the same attention on diesels. Your only major city in the republic is Dublin, and that is a mere pimple compared to the major cities of London, Birmingham, Leeds, and Manchester in England. The population of the Republic is only 3 million, the UK 65 million. This explains in part the emphasis on the future of diesel in the UK, and any remarks you make in this respect within the context of the Republic are just totally irrelevant.
Poppy ****. Everything here is just as relevant here as there. You are no more 'special'. We have politicians eager to hoodwink the motorist into paying another green tax. We embraced the economic benefits of diesel long before the UK with diesel accounting for more than 50% of the market since the mid 80's. We have manufacturers with heavy money tied up in PCP deals. We have dealers with millions of euro tied up in diesel stock, new and used. We have lots of old diesel machines still running. We have a huge reliance on oil fired domestic heating systems. Frankly, I find your comments offensive as well as ridiculous. Next you'll be saying your kids are more important than ours. Take such nonsense elsewhere.
 

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The whole 'diesel is dead and will be wiped off the planet overnight' thing is complete rubbish. Domestic heating systems and older (pre-emission control) diesel cars, vans, buses, trucks and even trains, create the bulk of nox emissions. To wipe out diesel values would expose dealers and manufacturers to huge losses on the pcp values they are committed to. Won't ever happen. What you will see is further tech from manufacturers on reducing nox, and a gradual reduction in older diesels through natural wastage and incentives, i.e. scrappage schemes. Diesel is far from dead, its only getting started.
I agree. I personally think I made a good choice buying the speciale before the end of march.

The government will definitely start asking people to replace OLD diesel cars, with incentives and so on, but I don't think we will see car like my Giulia being banned from London in within the next 4 years unless they offer big money to replace all of them
 

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Petrol (vs) Diesel

EDIT: See post #3 for corrected peak torque figures, I got my wires crossed reading the online manual.


I currently have a loan diesel Giulia (single exhaust so this is a 150HP model, torque being the same as 180HP as per manual - 380Nm : 150HP @ 4250 rpm, 180HP @ 3750 rpm) as opposed to my own 2.0 200HP Petrol Super (200HP, 330Nm @ 1750 rpm) . So I thought it would be good to do a comparison of the two engines and post my thoughts.

NOTE: This post is no way intended as one engine is better than the other but purely an objective comparison slightly tainted with my subjective experiences and preferences.
My impressions of the diesel are over 2 days, roughly 100miles with about 30 miles of motorway, 60 miles of A roads and 10 miles of town, using mainly N and D modes with the occasional A mode for testing purposes. As I know the Giulia already very well, I was able to zone in on the engine alone and filter out the infotainment, drive and handling aspects which are pretty much embedded in my sub-conscious.

STARTING/TAKE OFF: Diesel as expected sounds a bit clattery from cold start. On moving off with the engine cold, it continues to be a bit gruff until normal operating temperature is reached when it quietens down a lot. Strangely, the engine sounds quieter/more refined from outside than from inside the cabin at cold starts and initial take off, until engine warms up. This I find is a lot quieter and pokier than the C-class Diesel I drove a while ago which sounded like a tractor. The petrol in comparison is understandably quiet at start-up and take off, although the petrol Multi Air engine I find is a bit noisier/rougher than the 2.2JTS engine I owned before which was smooth as butter.

CRUISING/OVERTAKING: In steady cruising speeds, the engine is fairly refined and quiet and it is not easy to distinguish between the diesel and petrol. There is no diesel drone, with perhaps a slightly louder engine note that will give away it’s a diesel if you really pay attention, more so with stereo off. If throttle input is given from cruising speed, the engine note changes and it lets you know it’s a diesel, however it remains fairly refined. Power delivery is smooth and progressive similar to the petrol. There is more torque than the petrol obviously which shows in how strongly the diesel pulls, but with my petrol the peak torque comes is below 2000rpm where as in the 150hp diesel it comes in at 4250 rpm so the engine likes being revv’d a bit more than the petrol to do the same sporty overtaking/speed increase manoeuvres. Gearbox is the same and changes are smooth and progressive.

Drive modes: A is really sluggish, more so than the petrol. N is fine for day to use and normal driving. D is very responsive and quite fast, almost sporty (“almost” when compared to petrol). In D, the engine revs higher and harder and the note becomes a bit louder, but you always still know you are driving a diesel. And on that count, for the sake of sportiness I prefer the petrol which especially in D mode is proper sporty and rapid if you are prepared to say goodbye to fuel. I find the way power is delivered in the petrol and how the engine note sounds with sporty driving in N and D a lot more “engaging and emotional” when compared to the Diesel. The 150HP is actually pretty rapid in D mode surprisingly and quite easy to get to high speeds, the 180HP will certainly feel more quicker.
In terms of fuel economy, I don’t think there is a huge difference between the modes if driving steadily, maybe about 4 to 6mpg at the most. In the petrol though you can have as much as 10+mpg difference between A and D.

START/STOP EVO – Although I am not a big fan of SS, I tried it. SS is a lot more refined and tad faster on the petrol. With the diesel, it’s a bit laggy and starts/stops with a bit of an unrefined jolt (in comparison). For this reason I personally would never leave this function active on the diesel whereas I might occasionally on the petrol.

OTHER OBSERVATIONS:
The wind noise from around the doors/seals I feel with my petrol is definitely present in the loan car as well. I think the problem is either due to excessive door panel gap or inadequate compression of the door seals, which leads me to think it’s a design shortcoming. Wind noise from both cars is far more noticeable than my previous 159. If others including some Qf owners have not noticed this then either they have different door panel gaps, different door seals or else they are subjectively not feeling/hearing it. The noise is not too intrusive though but it is there.
The passenger seat (super model) has the same wobble/damped vibration on rough surfaces and cruising speeds when unoccupied. I have come to the conclusion, this is caused by the lightweight and slim seat design and the way it has been mounted. The back support part does not appear to be stiff enough and wobbles from seat base to the top. Another design issue IMO. Again not a major issue as passenger seat is usually occupied by my son or my bag. Solution is get Veloce or Speciale seats and of course Qf seats (haven’t heard any issues with these so far).

OVERALL IMPRESSION:
Even in the 150HP guise, the engine is surprisingly refined once warmed up compared to cars in the same class (MB, BMW) , only the Audi diesel I feel is more refined (and more boring). Drive, gear box and handling is exactly the same on both engines. In the 180HP guise, it will be a tad bit more quicker as the identical torque comes in a little earlier. With the same impressive handling and slick gearbox, I prefer driving the diesel in D mode majority of the time especially given fuel economy is still high 30’s or early 40’s.

Now, the big question: Would I swap the petrol for the diesel? SHORT ANSWER IS NO. Being a long term petrol head and doing less than 10k miles a year, I prefer the refinement of the petrol engine and the way the petrol delivers the power while feeling more sporty when demanded, at the cost of fuel economy which is the only down side. Having said that, this is probably the first diesel I have enjoyed driving and may end up buying when coupled with how the Giulia steers and handles, especially in the Speciale trim. The fuel economy despite rapid driving is very impressive too. Both cars are equally good and serve specific requirements and therefore quite subjective, even if this sounds a tad non-controversial! :rambo:
hi mate

good review ..
iv got the 2.2d 180 speciale.... fantastic car, and far more refined than my 2014 c220 amg sportplus which was also a great car.
I was just saying the other day that it really doesn't sound like a diesel and makes a nice noise (obviously not as nice petrol) when revved....
I would of liked the voloce , but diesel works better for , and it is still great performing car , which I'm sure the 2.0 petrol super is ...
 

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hi mate

good review ..
iv got the 2.2d 180 speciale.... fantastic car, and far more refined than my 2014 c220 amg sportplus which was also a great car.
I was just saying the other day that it really doesn't sound like a diesel and makes a nice noise (obviously not as nice petrol) when revved....
I would of liked the voloce , but diesel works better for , and it is still great performing car , which I'm sure the 2.0 petrol super is ...
what color did you get?
 

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Alfa red of course !

QUOTE=gmore01;16069769]
hi mate

good review ..
iv got the 2.2d 180 speciale.... fantastic car, and far more refined than my 2014 c220 amg sportplus which was also a great car.
I was just saying the other day that it really doesn't sound like a diesel and makes a nice noise (obviously not as nice petrol) when revved....
I would of liked the voloce , but diesel works better for , and it is still great performing car , which I'm sure the 2.0 petrol super is ...
what color did you get?[/QUOTE]
 
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