Death of the natural aspirated engine?

Mitchi

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So I was discussing this with my mates a couple of days ago.

We all know that in current times turbocharging is the new trend since it's become to a point where it's so effective you can pretty much turbocharge everything, get more power and torque and save fuel (when the turbine isn't spinning...). Legislations and laws pretty much make the NA engine extinct since you nowadays it's very hard to make it pass the emission tests.

But what do you guys think, when will the point arrive where we will no longer be able to get NA engines in our cars? When will these things become a story of the past? Have we already exceeded that point?

The reason for me asking this is because I've realised that pretty much all german manufacturers (with exceptions) have stopped producing them:
- Mercedes-Benz has dropped the 350 V6, it's currently only available with 4matic (only E class coupe I think?) but this will probably be dropped aswell very soon. As far as I'm concerned it was the last one they build.
- Audi has dropped its last NA engine (besides the R8, that is), the 2.8 FSI with the facelift of the A6 C7 in autumn 2014. Also note how it only produced 210 hp (speaking of it passing the regulations) whereas you could get more out of a M50B28 twenty years ago, and that engine didn't have direct fuel injection.
- BMW has no naturally aspirated engine left, also what you think of as a straight six are "only" four cylinders nowadays (x28i).
- Opel still has some naturally aspirated engines like the 1.6, but that's probably due to the fact that they don't build V8s and therefore it's easier for them to get the general companies fleets emissions down (same goes for french manufacturers).
- Porsche likes turbos, but cars like the 911 pretty much live from the NA engine. Interesting to see how this will go on in the future, since VAG can be used to get the fleets emissions down here aswell. Also, think of that four cylinder turbo Cayman coming soon.
- And Volkswagen has dropped all its naturally aspirated engines aswell besides the 1.0 3 cylinder in the Up!.

Speaking of which, this whole downsizing process and its goal of keeping the emissions down brought me to another part:
Ten or twenty years ago, you could just go to an Audi, BMW, Mercedes-Benz or Volkswagen dealership, get yourself a mid-sized V6/VR6/I6 that lasts half a million kilometers with good care and you're done.
Nowadays, you get engines like the 1.4 TSI which as far as I'm concernes is crap (sorry Narf and Perc!), since you have to be very careful with it, otherwise the chance of it breaking down before it reaches 100.000 km is quite big. Also, I've never seen a car with that engine that reached more than 200.000 km. Some are probably out there, but they are exceptions and won't nearly last as long as proper NA engines can. I don't want to pick on VAG here, it's just an example.I don't really think that turbocharged engines other manufacturers will do better in the future. BMW pretty much says their current (leased) cars are done after 150.000 km.
Now, since the reason of downsizing is to bring the emissions of a car down. But when more new cars/engines have to be produced to get the same mileage as with an NA engine, isn't this completely contraproductive in terms of overall emissions? Just think what needs to be done to produce a car... I hope you get my point.

Also, how is it on the North American market? I know that especially Californias emission regulations are pretty much the strictest you can find, but is the trend of the NA engine becoming extinct over there a thing aswell?

Would love to hear your thoughts on this.
 
Mazda seems to be going against the current with their continued focus on NA engines with their Skyactive line.

I can also still see a place for low displacement NA engines in the small budget cars, like the Up!, Ka, Picanto etc. since the Turbo ads cost and the Granny potting around town in second gear doesn't need more than 75 hp anyway.
 
I agree that FI is getting to be more mainstream but there are still a lot of big companies that don't much of it. Ford is only using Ecoboost for higher power applications, pretty much none of the Japanese are doing FI as mainstream, at least not stateside.

I think it's all moot, I can't see ICE being around as mainstream personal transportation for very long. Between Tesla and their tech and Toyota dumping all of their HFCV patents to public it looks like we are pretty much on track for useful electric in one form or another.
 
- And Volkswagen has dropped all its naturally aspirated engines aswell besides the 1.0 3 cylinder in the Up!.

Not quite. The two bottom petrols in the Polo still are N/A (most mainstream relevance), and then there's the 1.6 BiFuel (petrol/LPG) or 2.0 EcoFuel (CNG) in the Caddy, the petrol 2.0 in the T5, the 3.6 VR6 in the CC, and the petrol V6, V8, W12 Phaeton.

I agree with you though, these are mostly niche products. The key observation is "no N/A Golf", that already says it all.




Speaking of which, this whole downsizing process and its goal of keeping the emissions down brought me to another part:
Ten or twenty years ago, you could just go to an Audi, BMW, Mercedes-Benz or Volkswagen dealership, get yourself a mid-sized V6/VR6/I6 that lasts half a million kilometers with good care and you're done.
Nowadays, you get engines like the 1.4 TSI which as far as I'm concernes is crap (sorry Narf and Perc!), since you have to be very careful with it, otherwise the chance of it breaking down before it reaches 100.000 km is quite big. Also, I've never seen a car with that engine that reached more than 200.000 km. Some are probably out there, but they are exceptions and won't nearly last as long as proper NA engines can. I don't want to pick on VAG here, it's just an example.I don't really think that turbocharged engines other manufacturers will do better in the future. BMW pretty much says their current (leased) cars are done after 150.000 km.

Uhm, did you read a different article from the one I read? For the non-Germans, this article talks about how BMW Leasing wants someone who quit his leasing contract after 30000km to pay 20% of the list price of the car. Naive maths happens and you get 100% for 150000km.

That's not how this works. That's not how any of this works :no:

First, the depreciation of a car is not linear with its odometer. The first kilometre is BY FAR the most expensive. To use myself as an example, I bought my Eos for less than 50% list price at 27000km. Does that mean it'll be worthless at 52000km, ie maybe in time for Ringmeet? Don't give me a fiver then and try to buy it :shakefist:
Second, this is a financial services company making business with new and newish cars. To them, a 150000km car is indeed worthless because they cannot make any money off it. If the customer has by then paid for 100% of the car they make a nice profit selling the worthless car for a lot more than chump change.
 
While sad to see NA engines go, I can understand why as well. Much of naturally aspirated engines appeal comes from its more immediate reactions to throttle use. But with modern cars getting so heavy, the weight takes much of that away. I've test driven the N52B30 NA straight six I have in my 1er in several 1-, 3- and 5-series. And it feels quite lifeless to me in the 5er already.

Sound and response are the main things going for NA engine (for me at least), but with new cars being too heavy and too quiet I'd most likely go for a turbo model if I were looking for a new car..

Meanwhile, I let my BMWs sing to their NA hearts content. :cool:

 
While sad to see NA engines go, I can understand why as well. Much of naturally aspirated engines appeal comes from its more immediate reactions to throttle use. But with modern cars getting so heavy, the weight takes much of that away. I've test driven the N52B30 NA straight six I have in my 1er in several 1-, 3- and 5-series. And it feels quite lifeless to me in the 5er already.
That's a function of power and torque not really whether the car has forced induction or not. Sure FI can makes more of both out of same sized engine but that's a different conversation altogether. Also keep in mind that FI engines tend to be heavier than NA because of all the extra components.
 
Of course. That was a quick reply, and as such a fairly simplified one. In more powerful cars I'd still prefer NA and availability shows that significant part of buyers agree with me. But if talking about "normal" cars (and from Euro perspective of course) I'd rather have a 2 litre turbo than 3 litre NA engine with similar figures on most new cars. But I'm only talking about a car that most people would see as a useable daily driver.
 
I agree that FI is getting to be more mainstream but there are still a lot of big companies that don't much of it. Ford is only using Ecoboost for higher power applications, pretty much none of the Japanese are doing FI as mainstream, at least not stateside.
Ford in Europe and here is using EcoBoost in plenty of downsized engines, like the 1.0-litre three cylinder turbo in the Fiesta and Focus, then 1.6 EcoBoost in things like the Kuga and Mondeo.

I see NA engines becoming increasingly rare too. I had the thought a few years ago before all this forced induction in downsized applications took off. You couldn't buy a diesel without a turbo anywhere at the time (I think in Aus the last available NA diesel was the 4.2L six cylinder in 70 Series LandCruisers), and I thought why if all diesels are turbocharged, why aren't petrol engines? If they are more efficient, you get more power out of less displacement and fuel - why aren't more people doing it? Of course now nearly everyone is doing it.

The longevity concern is one that I do think of. I know mechanics and older people who immediately think of turbos as trouble makers. I know nothing about how engines work, but apart from having extra components to fail, is there really any reason why a turbo engine has to be less durable in the long term than an NA engine? Obviously boost puts more pressure on everything (ha pun), but surely engines can be designed to handle this if that's what they know they will be running?

If I was buying a new car which I intended to keep for a long time, a small turbo engine would put me off to an extent. If I was buying a car second hand with high mileage, as I tend to do, a small turbo engine would again make me wary. I don't even know enough to know if my fears are founded or not.
 
You just have to look at the old D15 engines in EG civics. 100,000 kms is considered low. I'm sure if it was FI it wouldn't have that kind of reliability.

Then again, it's not like FI is an indicator of longevity. I've seen many RB26's with flawless compression over 100,000 kms. Good ol cast iron blocks....

edit: I finally understand what it's like to be "old". When the time comes when NA engines are things of the past, I'll be telling all the teenagers how great my S54 sounded.
 
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The longevity concern is one that I do think of. I know mechanics and older people who immediately think of turbos as trouble makers. I know nothing about how engines work, but apart from having extra components to fail, is there really any reason why a turbo engine has to be less durable in the long term than an NA engine? Obviously boost puts more pressure on everything (ha pun), but surely engines can be designed to handle this if that's what they know they will be running?
It's not so much extra parts that you have to worry about but rather the kind of stress these parts are under. Turbine/compressor spin at 100K+ RPMS, that is a lot of heat and a lot of friction and physics is a stone cold bitch. Of course modern water cooled turbos are much better than old oil cooled set up but.... There is also design to consider, Subaru has an infamous issue in their old Forester XT models where the banjo bolt that would oil the turbo was too restrictive and if you drove like one would drive a turbocharged Subaru it had a tendency to starve the turbo of oil and destroy it. While I'm not saying that NA engines are immune to shitty design they do tend to have much looser tolerances because of relatively low speed.
 
Speaking of which, this whole downsizing process and its goal of keeping the emissions down brought me to another part:
Ten or twenty years ago, you could just go to an Audi, BMW, Mercedes-Benz or Volkswagen dealership, get yourself a mid-sized V6/VR6/I6 that lasts half a million kilometers with good care and you're done.
Nowadays, you get engines like the 1.4 TSI which as far as I'm concernes is crap (sorry Narf and Perc!), since you have to be very careful with it, otherwise the chance of it breaking down before it reaches 100.000 km is quite big. Also, I've never seen a car with that engine that reached more than 200.000 km. Some are probably out there, but they are exceptions and won't nearly last as long as proper NA engines can. I don't want to pick on VAG here, it's just an example.I don't really think that turbocharged engines other manufacturers will do better in the future. BMW pretty much says their current (leased) cars are done after 150.000 km.

you could go to audi, and buy a worn out car, with leaking suspension, wrecked bushes and rust holes all over, but the engine still went, so they sold it, and didn't care you were a liability on the road
i'm glad those times are over. drive a good car, or drive no car...
i have good brakes, and i use them! i don't want no 20yo car crashing in my ass because they owner doesn't want to spend the money on a new car.

Now, since the reason of downsizing is to bring the emissions of a car down. But when more new cars/engines have to be produced to get the same mileage as with an NA engine, isn't this completely contraproductive in terms of overall emissions? Just think what needs to be done to produce a car... I hope you get my point.

everyone must have a job. and to have a job for everyone, a lot of production is needed. i prefer them using artificial tricks to keep the carpark younger, than that they let those people make useless junk no one needs (aka made in china). they're also only iron. making cars gives as much emission as making metal cabinets...
 
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