Discussion
First diesel I drove was in a Ford Sierra. It was a naturally aspirated four cylinder 2.3 making 66bhp and taking about 20 seconds to get to 60. That was a work vehicle.
Then I had a 306 XND hire car, 1.9 four cylinder, not much quicker than the Sierra. I picked it up in Kendal and needed to be in Fort William in a legally infeasible time. This was before the proliferation of speed cameras. I got there on time and rather enjoyed it. Someone at work had a ZX Volcane TD I rather envied, despite him being a dick.
When my wife wanted to get her licence, I bought her a Citroen AX 1.5d for her birthday. Not boasting here, this was a £600 shed, but it got her through her test and literally the weekend after she passed she got rid of it for an MX-5. I was proud. Anyway, that was a nasty little NA diesel, but quite a fun little car despite it, and appeared to run on fresh air.
The next time I was exposed to Satan’s fuel was 2016, when I wanted to replace my 9-5 Aero estate with something similar and realised that people had just stopped buying big petrol estate cars. I ended up with a Mercedes E class estate with a 3 litre V6 turbodiesel. It was more refined than the Saab, but slower, so I had it remapped. That was impressive. That died on me, injector failure at 160k, possibly not entirely unrelated to the remap, so I bought a 2010 E350CDI. That was great, quiet, civilised, less of a barge than the previous one, but also an unreliable money pit.
I lost confidence in the Merc because it kept costing me money and causing me to call the AA, and the final straw was Mr Khan’s threats to expand the ULEZ. So last weekend I bought a 2016 335d GT. I seriously considered a 335i, but nobody bought them new and I preferred having a choice of cars.
I’ve just driven it from Surrey to Lancashire. Plan was to stick it in eco-toss mode, set the cruise to 70, and see what it did, but the M25 was broken, I had a Satnav alternative route magical mystery tour through the suburbs of West London (the stop-start stuff works), and a frustrating drive of the “I’m at exactly 70, how have you caught me up yet now sit alongside me?” variety. Too much traffic and too many morons to sit at constant speed. Despite that, it did 45mpg. It claims 48, but it lies. I’ll take that. I came off the motorway, filled it up and calculated the mpg, then drove it the rest of the way home like an a
hole, in Sport, which got about 25mpg.
Looking at the progression over nearly 30 years, diesels have improved beyond all recognition. They were always economical, but they used to be awful. They’re now a dead end. Killed by the costs of emissions compliance and likely buried by electric cars. I think the engine in the BMW *35d is about the peak of them. Maybe you could make an argument for the 8 or 10 cylinder turbodiesels which appeared for a while, but 60 in under 5 seconds and mid forties to the gallon with six cylinder refinement is a fairly sweet spot. They’re going out at the best they’ve been.
But petrol engines. That’s a longer and more complicated history. They’re also about to be killed off by EVs, and while they’ve been getting objectively better until the end, subjectively not so much, I think. Nobody sane looks back fondly at NA diesels, but if you compare the state of the art petrol drivetrain in the new AMG E class, all turbocharged and hybridised - there are 60 year old petrol engines which are more exciting. Less powerful, much less efficient, much dirtier, but if someone else was paying the bills, would you really rather take a 2.0 hybrid turbo 4 for a drive over a 30 year old Ferrari or Lamborghini V12? Would you really get more joy from a Golf R than a DC5 Integra or a BDA RS2000?
Maybe you would.
If not, if the state of the art isn’t for you, what was the peak?
Then I had a 306 XND hire car, 1.9 four cylinder, not much quicker than the Sierra. I picked it up in Kendal and needed to be in Fort William in a legally infeasible time. This was before the proliferation of speed cameras. I got there on time and rather enjoyed it. Someone at work had a ZX Volcane TD I rather envied, despite him being a dick.
When my wife wanted to get her licence, I bought her a Citroen AX 1.5d for her birthday. Not boasting here, this was a £600 shed, but it got her through her test and literally the weekend after she passed she got rid of it for an MX-5. I was proud. Anyway, that was a nasty little NA diesel, but quite a fun little car despite it, and appeared to run on fresh air.
The next time I was exposed to Satan’s fuel was 2016, when I wanted to replace my 9-5 Aero estate with something similar and realised that people had just stopped buying big petrol estate cars. I ended up with a Mercedes E class estate with a 3 litre V6 turbodiesel. It was more refined than the Saab, but slower, so I had it remapped. That was impressive. That died on me, injector failure at 160k, possibly not entirely unrelated to the remap, so I bought a 2010 E350CDI. That was great, quiet, civilised, less of a barge than the previous one, but also an unreliable money pit.
I lost confidence in the Merc because it kept costing me money and causing me to call the AA, and the final straw was Mr Khan’s threats to expand the ULEZ. So last weekend I bought a 2016 335d GT. I seriously considered a 335i, but nobody bought them new and I preferred having a choice of cars.
I’ve just driven it from Surrey to Lancashire. Plan was to stick it in eco-toss mode, set the cruise to 70, and see what it did, but the M25 was broken, I had a Satnav alternative route magical mystery tour through the suburbs of West London (the stop-start stuff works), and a frustrating drive of the “I’m at exactly 70, how have you caught me up yet now sit alongside me?” variety. Too much traffic and too many morons to sit at constant speed. Despite that, it did 45mpg. It claims 48, but it lies. I’ll take that. I came off the motorway, filled it up and calculated the mpg, then drove it the rest of the way home like an a
hole, in Sport, which got about 25mpg. Looking at the progression over nearly 30 years, diesels have improved beyond all recognition. They were always economical, but they used to be awful. They’re now a dead end. Killed by the costs of emissions compliance and likely buried by electric cars. I think the engine in the BMW *35d is about the peak of them. Maybe you could make an argument for the 8 or 10 cylinder turbodiesels which appeared for a while, but 60 in under 5 seconds and mid forties to the gallon with six cylinder refinement is a fairly sweet spot. They’re going out at the best they’ve been.
But petrol engines. That’s a longer and more complicated history. They’re also about to be killed off by EVs, and while they’ve been getting objectively better until the end, subjectively not so much, I think. Nobody sane looks back fondly at NA diesels, but if you compare the state of the art petrol drivetrain in the new AMG E class, all turbocharged and hybridised - there are 60 year old petrol engines which are more exciting. Less powerful, much less efficient, much dirtier, but if someone else was paying the bills, would you really rather take a 2.0 hybrid turbo 4 for a drive over a 30 year old Ferrari or Lamborghini V12? Would you really get more joy from a Golf R than a DC5 Integra or a BDA RS2000?
Maybe you would.
If not, if the state of the art isn’t for you, what was the peak?
While petrols have lost character and sound due to turbocharging, injection and more recently OPF's. Diesels have only improved over the years with turbo's, intercoolers and DPF's.
The 35/40d engine is mightily impressive, but to be honest so is the 40i's performance. The latter has just lost more since the days of the 3.0i NA engine.
The 35/40d engine is mightily impressive, but to be honest so is the 40i's performance. The latter has just lost more since the days of the 3.0i NA engine.
Diesels will have definitely peaked because they are on their way out and manufacturers less inclined to develop new ones. The BMW six is great, I’ve had two but I believe the VAG 4.0 V8 is incredible.
Petrols are getting more and more efficient and powerful but there is a question over character v technical competence.
I’m a dinosaur and absolutely love my M156 6.2 V8. It will be the peak petrol engine I’m likely to own, but it isn’t peak petrol engine generally. Not far off mind.
Petrols are getting more and more efficient and powerful but there is a question over character v technical competence.
I’m a dinosaur and absolutely love my M156 6.2 V8. It will be the peak petrol engine I’m likely to own, but it isn’t peak petrol engine generally. Not far off mind.
The current three-cylinder 998cc turbo'd petrol engines can deliver impressive performance and economy. I've just bought a Fiesta with one, 123bhp so reasonably nippy and mid 40s mpg when laden with all our holiday gear. Just a shame it's mated to a mediocre gearbox as it needs a lot of stirring to keep it on the boil; not a huge problem though as it's mostly used as a town runabout.
It's an interesting contrast to the 4.2 V8 in my A8 and the 1.5 four-pot in my Riley; one delivers 330bhp, the other around 80bhp. Economy for both is +/- 25mpg making the 'three' the overall best of the bunch.
It's an interesting contrast to the 4.2 V8 in my A8 and the 1.5 four-pot in my Riley; one delivers 330bhp, the other around 80bhp. Economy for both is +/- 25mpg making the 'three' the overall best of the bunch.
I think over the years both diesels and petrols have got more refined, more powerful, mostly more efficient and much less characterful. The difference is that petrols of old often had a character that was generally considered pleasant whereas the character of oil diesels was pretty horrible.
Depends what your criteria are. The 90s and (early/mid?) 00s were probably the peak for petrol in terms of cylinder/capacity silliness before downsizing and forced induction started taking hold properly.
Since then it’s felt a bit like managed decline with the focus being “how can we still make this smaller engine exciting/desirable” rather than “how can we achieve the maximum performance without restrictions”.
It’s testament to engineers that they’ve managed to keep increasing power outputs, but a 2 litre 4 pot with a silly specific output isn’t quite as evocative as the big V8s/10s/12s of old.
Since then it’s felt a bit like managed decline with the focus being “how can we still make this smaller engine exciting/desirable” rather than “how can we achieve the maximum performance without restrictions”.
It’s testament to engineers that they’ve managed to keep increasing power outputs, but a 2 litre 4 pot with a silly specific output isn’t quite as evocative as the big V8s/10s/12s of old.
It depends what you define as the peak, but for me the last gasp of big naturally aspirated engines was peak excitement. The V8, V10 and V12 monsters that delivered the spine tingling noise and the jet like thrust will always be the most admired by me, and whilst turbos are brilliant at the day to day stuff and the economy, they just don't appeal for fun.
Peak engine… depends what you mean by that really. For me it’s lumped into what is actually peak driving experience. And again, for me, that’s big NA V8/10/12s in cars that don’t drive for you with tons of driver aids. I’m happy with a manual gearbox and a single button to completely disengage traction control.
Mouse Rat said:
I was giving a mate a lift in my E350d. He has a fast EV and VAG tuned 2.0 petrol.
He triggered a similar conversation that there's nothing like a good 6 cylinder turbo diesel for daily duties.
I agreed. Peak engine
Why is a 6 cylinder Diesel better for daily duties than an EV? He triggered a similar conversation that there's nothing like a good 6 cylinder turbo diesel for daily duties.
I agreed. Peak engine
I preferred a bloomin Renault Zoe to my 2020 E350d for daily driving due to it being more responsive and precise. Sure the Mercedes would leave it for dust when trying or motorway ++ speeds, but around town type driving, then no contest, Zoe is just more pleasant to drive (I'm talking drivetrain here as opposed to the rest of the car around it).
plfrench said:
Why is a 6 cylinder Diesel better for daily duties than an EV?
I preferred a bloomin Renault Zoe to my 2020 E350d for daily driving due to it being more responsive and precise. Sure the Mercedes would leave it for dust when trying or motorway ++ speeds, but around town type driving, then no contest, Zoe is just more pleasant to drive (I'm talking drivetrain here as opposed to the rest of the car around it).
I'm not anti-EV, but a 6 cylinder diesel can do pretty much everything. Tow, long distances, good range, ease/speed of refuelling, reasonable running costs, quick, smooth, longevity, not expensive on the used market, can power everything from a convertible to a 7 seat SUV and excel wherever it's implemented.I preferred a bloomin Renault Zoe to my 2020 E350d for daily driving due to it being more responsive and precise. Sure the Mercedes would leave it for dust when trying or motorway ++ speeds, but around town type driving, then no contest, Zoe is just more pleasant to drive (I'm talking drivetrain here as opposed to the rest of the car around it).
kambites said:
I think over the years both diesels and petrols have got more refined, more powerful, mostly more efficient and much less characterful. The difference is that petrols of old often had a character that was generally considered pleasant whereas the character of oil diesels was pretty horrible.
Yes, I think that’s probably true. The best engines that I’ve actually owned. .
BMW 40d, probably the best mix of power and fuel consumption. 306bhp and still did mid 30s mpg in an X6.
Favourite engine was probably the bmw 3.0 straight six petrol, I had a few cars with it and it was just a lovely smooth thing that never seemed to go wrong, while being surprisingly economical.
I had bmw 645 with the flawed 4.4l V8, I loved it but it was easily the least reliable/most I’ve paid fixing a car.
I do have a fondness for NA V8s, just not that particular one!
BMW 40d, probably the best mix of power and fuel consumption. 306bhp and still did mid 30s mpg in an X6.
Favourite engine was probably the bmw 3.0 straight six petrol, I had a few cars with it and it was just a lovely smooth thing that never seemed to go wrong, while being surprisingly economical.
I had bmw 645 with the flawed 4.4l V8, I loved it but it was easily the least reliable/most I’ve paid fixing a car.
I do have a fondness for NA V8s, just not that particular one!
It's probably the BMW N52 for me, so one of the last N/A straight 6s they did. Plenty of torque for pooling around town, always smooth and starts snarling at you if you poke it with a big stick, then races to the redline as a proper engine should. Mostly reliable, and great on fuel when you want them to be.
Being an engine man I've mostly looked at the engine before the car to be fair. I've had a few diesel engines that have impressed me(E90 330d/F13 640d/GLC350d), but the peak for me is the 2.9 straight 6 twin turbo diesel engine that is in the GLE400d. It is lovely and smooth, punchy and it even makes a reasonable noise from inside I reckon(it would be even better in something that weighs less than 2300kg too!). I did also love the 3.0 straight 6 twin turbo in the 640d though.
Petrol wise I've loved almost all of them I've had. Peak wise for me it would be between the V8 4.8 NA engine in the X5 4.8iS, or the 3.0 straight 6 twin turbo in the M4. However I also liked the V8 4.5 NA in the Cerbera, plus the 4.0 V8 NA in the M3 had some qualities but that would suit a lighter car for me.
The 3.0 straight 6 NA and the 3.2 straight 6 NA in the E90 330i/Z4M deserve a mention too. The 3.7 V6 NA in my 370Z makes a nice noise, but I wouldn't describe it as being anywhere near the peak in comparison to the other engines I've had though.
Petrol wise I've loved almost all of them I've had. Peak wise for me it would be between the V8 4.8 NA engine in the X5 4.8iS, or the 3.0 straight 6 twin turbo in the M4. However I also liked the V8 4.5 NA in the Cerbera, plus the 4.0 V8 NA in the M3 had some qualities but that would suit a lighter car for me.
The 3.0 straight 6 NA and the 3.2 straight 6 NA in the E90 330i/Z4M deserve a mention too. The 3.7 V6 NA in my 370Z makes a nice noise, but I wouldn't describe it as being anywhere near the peak in comparison to the other engines I've had though.
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