The government have won. Selling my diesel for a petrol.....
Discussion
The Crack Fox said:
I don't really give a f
k and nor, I daresay, do the other millions of diesel owners on the road. I do 20k a year, get 44MPG in a big, wafty, reliable car that I am in no hurry to offload. 
sgtbash said:
Ninja59 said:
Bit unfair the 3.0 diesel 335D is an older generation design M57 v a newer 335i N54 series engine...
Exactly. The newer 335d's have loads more power.
And the N54 has been replaced by the N55.
Your point is what exactly?!? Other than to argue against minutiae that isn't actually core to the point I was making, which is to do with (the lack of) relative power-band width (as % of total rpm) vs an equivalent petrol engine.
havoc said:
And the N54 has been replaced by the N55.
Your point is what exactly?!? Other than to argue against minutiae that isn't actually core to the point I was making, which is to do with (the lack of) relative power-band width (as % of total rpm) vs an equivalent petrol engine.
I get your point about power band width, but the reality back in the real world again is that how often would you need to rev out that far? Furthermore, with the majority of engines these days of the 6 pot nature from BMW come with the ZF8. Even the smaller engines can work quite effectively combined with a ZF8.
Furthermore, sitting behind an N57 regularly whilst the power band width might be short that is all it needs to get to the relevant speed limits and sits at 80 at 2k rpm very happily.
Having listened to a few owners of 640D's who have driven 640i's. So fairly comparable they said there might be a "slight" minor advantage to a 40i in terms of pace (but official times are exactly the same), but the only things is it possibly sounds a tiny bit better being petrol but the MPG is much worse.
What I am actually saying is I somewhat agree with you, but combined to a ZF8 that has been driven for a while with the same driver the differences are negligible and for a significant proportion of the time the ZF8 does very smooth changes anyway.
Ninja59 said:
What I am actually saying is I somewhat agree with you, but combined to a ZF8 that has been driven for a while with the same driver the differences are negligible and for a significant proportion of the time the ZF8 does very smooth changes anyway.
And when dealing with modern multi-gear automatic boxes, I agree with you - a diesel engine mated to one of these is a very effective piece of kit....it's just not necessarily very engaging or enjoyable, at least not vs the equivalent petrol-plus-manual.
My original argument appears to have been lost in the mists of the thread, but I did qualify it originally by excluding the modern 'executive' 8/9-speed autos, which seem perfectly designed for a diesel. I only raised the 6-pot diesels (in this case I found a BMW graph, but the same could apply to JLR, Audi or Merc) in case some smart-alec tried to argue that narrow power-bands were only an issue in 4-pot diesels.
bmwmike said:
Pica-Pica said:
NOx of Euro 6 are pretty close for diesel and petrols, but CO2 are about half for diesel.
Not sure I'd call it pretty close looking at this article, but no doubt huge improvement's to both SI and CI engines over the years.Disclaimer.. I only skim read and looked at the pretty graph
https://www.theengineer.co.uk/fact-check-are-diese...
Agreed that is test measurement before anyone comments about real life figures, which none of us know for the whole gamut of cars available.
sgtbash said:
Ninja59 said:
Bit unfair the 3.0 diesel 335D is an older generation design M57 v a newer 335i N54 series engine...
Exactly. The newer 335d's have loads more power.Ninja59 said:
havoc said:
And the N54 has been replaced by the N55.
Your point is what exactly?!? Other than to argue against minutiae that isn't actually core to the point I was making, which is to do with (the lack of) relative power-band width (as % of total rpm) vs an equivalent petrol engine.
I get your point about power band width, but the reality back in the real world again is that how often would you need to rev out that far? Furthermore, with the majority of engines these days of the 6 pot nature from BMW come with the ZF8. Even the smaller engines can work quite effectively combined with a ZF8.
Furthermore, sitting behind an N57 regularly whilst the power band width might be short that is all it needs to get to the relevant speed limits and sits at 80 at 2k rpm very happily.
Having listened to a few owners of 640D's who have driven 640i's. So fairly comparable they said there might be a "slight" minor advantage to a 40i in terms of pace (but official times are exactly the same), but the only things is it possibly sounds a tiny bit better being petrol but the MPG is much worse.
What I am actually saying is I somewhat agree with you, but combined to a ZF8 that has been driven for a while with the same driver the differences are negligible and for a significant proportion of the time the ZF8 does very smooth changes anyway.
Ninja59 said:
At least compare apples with apples from the same bloody generation!
I get your point about power band width, but the reality back in the real world again is that how often would you need to rev out that far? Furthermore, with the majority of engines these days of the 6 pot nature from BMW come with the ZF8. Even the smaller engines can work quite effectively combined with a ZF8.
Furthermore, sitting behind an N57 regularly whilst the power band width might be short that is all it needs to get to the relevant speed limits and sits at 80 at 2k rpm very happily.
Having listened to a few owners of 640D's who have driven 640i's. So fairly comparable they said there might be a "slight" minor advantage to a 40i in terms of pace (but official times are exactly the same), but the only things is it possibly sounds a tiny bit better being petrol but the MPG is much worse.
What I am actually saying is I somewhat agree with you, but combined to a ZF8 that has been driven for a while with the same driver the differences are negligible and for a significant proportion of the time the ZF8 does very smooth changes anyway.
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and an all round better car.I get your point about power band width, but the reality back in the real world again is that how often would you need to rev out that far? Furthermore, with the majority of engines these days of the 6 pot nature from BMW come with the ZF8. Even the smaller engines can work quite effectively combined with a ZF8.
Furthermore, sitting behind an N57 regularly whilst the power band width might be short that is all it needs to get to the relevant speed limits and sits at 80 at 2k rpm very happily.
Having listened to a few owners of 640D's who have driven 640i's. So fairly comparable they said there might be a "slight" minor advantage to a 40i in terms of pace (but official times are exactly the same), but the only things is it possibly sounds a tiny bit better being petrol but the MPG is much worse.
What I am actually saying is I somewhat agree with you, but combined to a ZF8 that has been driven for a while with the same driver the differences are negligible and for a significant proportion of the time the ZF8 does very smooth changes anyway.
Pica-Pica said:
sgtbash said:
Ninja59 said:
Bit unfair the 3.0 diesel 335D is an older generation design M57 v a newer 335i N54 series engine...
Exactly. The newer 335d's have loads more power.To compare the engines based on PWR at set revs would be as meaningless a comparative measure as forcing a petrol car driver to change gear at 4,000rpm, and seeing if he could match the same car but with a diesel lump.
liner33 said:
The Crack Fox said:
I don't really give a f
k and nor, I daresay, do the other millions of diesel owners on the road. I do 20k a year, get 44MPG in a big, wafty, reliable car that I am in no hurry to offload. In the thousands.
Which won't happen.
New diesels, sure, old diesels, Governments will continue to operate scrappage schemes.
Fine on a 1997 Golf Mk4, maybe not so much use on a 2011 535d.
Ares said:
No, that would be pointless. Petrol engines need revs. Diesel engines do not. Some 'ultimate driving gods' may feel the need to rev beyond 7/8,000 rpm to get the full driving experience, but it makes no difference to real world pace, ceteris paribus.
To compare the engines based on PWR at set revs would be as meaningless a comparative measure as forcing a petrol car driver to change gear at 4,000rpm, and seeing if he could match the same car but with a diesel lump.
I think you must have missed the bit about % of max rpm, not at set revs. So a diesel at 2500rpm compared with the petrol at 3750 rpm.To compare the engines based on PWR at set revs would be as meaningless a comparative measure as forcing a petrol car driver to change gear at 4,000rpm, and seeing if he could match the same car but with a diesel lump.
KevinCamaroSS said:
Ares said:
No, that would be pointless. Petrol engines need revs. Diesel engines do not. Some 'ultimate driving gods' may feel the need to rev beyond 7/8,000 rpm to get the full driving experience, but it makes no difference to real world pace, ceteris paribus.
To compare the engines based on PWR at set revs would be as meaningless a comparative measure as forcing a petrol car driver to change gear at 4,000rpm, and seeing if he could match the same car but with a diesel lump.
I think you must have missed the bit about % of max rpm, not at set revs. So a diesel at 2500rpm compared with the petrol at 3750 rpm.To compare the engines based on PWR at set revs would be as meaningless a comparative measure as forcing a petrol car driver to change gear at 4,000rpm, and seeing if he could match the same car but with a diesel lump.
Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and an all round better car.
Here we go again! HahaWhat you meant to say was...
Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and I preferred it.
I'm only saying that as you said 'better' again. 
Personally I got a bit bored with my 535d, swapped for a 335d thinking it would be sportier and then realised it was the fact it was diesel. Swapped for the 335i and loved it.
However, was then lent the new NA 330i with 272hp and realised I loved that more.
I agree the diesel 35d/40d gives the perception of being quicker, I though that when I jumped to the 335i from the 335d, but once I got used to the 335i it was actually a bit quicker.
Remapped it was stonkingly fast.
It was also about 5mpg behind the 335d like for like. So bugger all.
I should just add, I would have another E61 today, and happily have a diesel, but can't see the point of the 535d really, the 530d gets much better economy and is good enough for what that car does imho. A 530i would be a nice choice too.
Edited by gizlaroc on Monday 29th January 19:17
my bold
BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and an all round better car.
No, it’s not. The absolute figures are very close to one another. Those figures are un-arguable.BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
Prinny said:
No, it’s not. The absolute figures are very close to one another. Those figures are un-arguable.
BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
Bingo. BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
Many of us don't buy something like a 6 series to be a motorway cruiser though, some just don't seem to get that.
xjay1337 said:
gizlaroc said:
Bingo.
Many of us don't buy something like a 6 series to be a motorway cruiser though, some just don't seem to get that.
Fair point.Many of us don't buy something like a 6 series to be a motorway cruiser though, some just don't seem to get that.
What else would you buy a 6 series for though?
OK, I’m cheating, but this is why I bought mine.
I have a 7-series to do motorway cruising in.
Prinny said:
my bold
BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
What figures? 0-60? Pointless.Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and an all round better car.
No, it’s not. The absolute figures are very close to one another. Those figures are un-arguable.BMW’s (petrol) turbocharging ethos has for many years been about replicating the feel & mannerisms of a v8 from the turbocharged i6. Indeed, this was how the x35i engine was initially pushed.
It would be quite possible by playing about with wastegates & bleed pressures to make the x35i engine feel a lot more “boosty”, much more old-school. That was never their intention.
What you’re describing as “much quicker” is the delta in acceleration - the diesel is much more lag-boost-change gear, (repeat) than the petrol, and we humans are very much susceptible to this as a measure of acceleration feeling “quick”.
The body is not especially good at measuring acceleration - the ‘snap’ of being pressed back into your seat is what you’re feeling, and the x35d has a bigger ‘snap’ is all.
Remember back when the Peugeot 306dTurbo was the hatch wunderkind? It wasn’t actually that quick, but that shove as the turbo came on song was what sold that car to so many.
I do agree with you that the 640d is probably the better day to day car for the UK though.
You may well be right, the 35i/40i was never designed to be high performance, otherwise it would maybe have been quicker...but in every day driving, the 640d is quicker, partly as it's fit with the gearbox is better, partly because whilst it has the same BHP, it has getting close to 50% more torque and a more usable power curve.
Bear in mind, with modern twin turbo diesels, there isn't a 306 dTurbo like shove anymore like there was.
gizlaroc said:
Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and an all round better car.
Here we go again! HahaWhat you meant to say was...
Ares said:
Actually, as some that had a 640d, and drove a 640i for a weekend, the 640d is noticeably quicker and I preferred it.
Personally I got a bit bored with my 535d, swapped for a 335d thinking it would be sportier and then realised it was the fact it was diesel. Swapped for the 335i and loved it. However, was then lent the new NA 330i with 272hp and realised I loved that more.
I agree the diesel 35d/40d gives the perception of being quicker, I though that when I jumped to the 335i from the 335d, but once I got used to the 335i it was actually a bit quicker.
Remapped it was stonkingly fast.
It was also about 5mpg behind the 335d like for like. So bugger all.
I should just add, I would have another E61 today, and happily have a diesel, but can't see the point of the 535d really, the 530d gets much better economy and is good enough for what that car does imho. A 530i would be a nice choice too.
But as a car, the 640d is the better car. Faster, more frugal (10mpg better, 15mpg on a run), suits the gearbox better.
It just, for some, uses the wrong fuel. That is why it will never be classed, by some, as a better car.
...oh, and I had my 640d 'remapped' too....stonkingly-er fast-er
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