The "which sort of engine" dilemma

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jamesrt

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#247831 25-Feb-2019 16:24

OK, I'm unashamedly an IT Geek; that does not make me a "Petrol Head" automatically - I know for some people the two spheres overlap, so reaching out...

"We" (family) are considering upgrading out main vehicle. Assume I know little about cars, and you won't be too far wrong.

If I was to compare two different cars, the "Model A" from Manufacturer A, and the "Model B" from Manufacturer B, then there are a couple of significant differences that I don't really understand the pros and cons of.

The "Model A" takes 91 octane petrol, in a "standard" 2.0L engine; the "Model B" takes 95 octane in a 1.2L Turbo. Both "A" and "B" have very similar consumption figures supplied by their makers - "A" at 6.3L/100Km, and "B" at 6.4L/100Km.

So, everything else being equal, why would I purchase a vehicle with an engine that requires more expensive petrol (95 vs 91) when at around $0.10c/litre for the difference, the "smaller" engine car will cost around $5.00 more to fill. With both cars having similar manufacturers consumption figures, they'll both use about the same amount of petrol with use - the "smaller" engine doesn't really seem to be saving anything there.

Or have I missed something obvious?

(And as I'm a NOT a "boy racer" type, I don't care if the "turbo" will cause that car to get from 0 to 100 at 1/2 second faster than the other, or whatever...)

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#2186997 25-Feb-2019 16:32

I would just drive both A and B to see which one I liked.

I'd take consumption figure with a grain of salt, but for these two, you'd probably be right in thinking they are about the same, though in the real world, they won't be 6.4/6.5 per 100km unless you are pretty much open road driving the whole time.

What I would do - find the one I like the look of, the feel of, the toys you get (important for a geek) and the after sales care, then worry about a minuscule difference in fuel usage.

As for 1.2 turbo vs 2L Naturally aspirated, they'll probably work about the same - the turbo may feel a little bit 'faster', but maybe not. We drove a 1.6 Turbo SUV (Peugeot 3008) around Europe last year, and it had plenty of pickup and I never felt short of power or speed. I have a 2L Diesel here (just bought it) and am also impressed with it's torque and speed (ever had a Diesel before).

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#2187005 25-Feb-2019 16:47

Personally I find cars that require 95 octane fuel or above are a PITA. Gull is cheapest in our area but it only has 98. When there is a ‘special’ price on at a petrol station it will invariably be only 91 that has dropped.

While turbos are reliable these days they do add a level of complication. Some turbos also have a shorter service interval (Hyundai Veloster a prime example @ 7500km/6 months).

You may also find the smaller capacity engine has to rev a little higher.

Despite all the above, one of our cars is a 1.5 turbo Ford Focus.

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Aredwood

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#2187010 25-Feb-2019 17:22

Without knowing more, get the 2L NA car. As 95/98 octane will continue to get more expensive, and some petrol stations are even beginning to scale back their sales of it. I predict that it wont be long until some petrol stations stop selling it completely. And only sell 91 and diesel.

I have seen a couple of Mobil stations, that used to have just 2 pumps that sold diesel. They have swapped all of the pumps that used to sell 95, to instead sell diesel. And the 2 original diesel pumps are now for 95.

Insurance companies normally charge higher premiums on petrol turbo vehicles.

1.2L car might be better if you do alot of driving in rush hour traffic. But if that is the case, then consider an EV, hybrid, or even diesel. As my diesel van uses hardly any diesel when stuck in traffic (so much so, that the engine wont warm up properly when the heater is on). While having the aircon running doesn't seem to affect fuel usage much (and even if it did, I wouldn't have to pay road tax to use the aircon) While almost everyone I know who has a petrol car, complains about the amount of petrol that the aircon uses.

Bung

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#2187081 25-Feb-2019 20:28

jamesrt:
If I was to compare two different cars, the "Model A" from Manufacturer A, and the "Model B" from Manufacturer B, then there are a couple of significant differences that I don't really understand the pros and cons of.

The "Model A" takes 91 octane petrol, in a "standard" 2.0L engine; the "Model B" takes 95 octane in a 1.2L Turbo. Both "A" and "B" have very similar consumption figures supplied by their makers - "A" at 6.3L/100Km, and "B" at 6.4L/100Km.

I would try to look further than "official" consumption figures. My initial prejudice would doubt 6.3l/100km for a 2.0l unless it's more sophisticated that the standard engines found in most vehicles. You might find the model on this site https://www.honestjohn.co.uk/real-mpg/

Technofreak

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#2187083 25-Feb-2019 20:36

My initial thoughts would be to go with a 2 litre engine normally aspirated engine over a 1.2 litre turbo charged engine.

As a rule the bigger engine will be less stressed than the smaller engine and should give better service.

I say should, because there can be exceptions to every rule. Some make/models of engines are known to give better/worse service than other makes models.

In the example you have quoted the smaller turbo charged engine is probably producing similar power to the larger non turbo charged engine, hence the similar fuel consumption assuming both vehicles are of a similar size and weight.

In fact a larger engine can be as fuel efficient as a smaller engine. Some on here will remember the SD1 Rover. It was made with a 2.3 and 2.6 litre straight six engines and 3.5 litre V8. I remember reading the 3.5 V8 was as economical if not more economical than the smaller straight six engines.

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alasta

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#2187087 25-Feb-2019 20:43

Is the 1.2 litre a three or four cylinder? Do the two engines have similar power & torque outputs? Be aware that the turbocharged engine will probably reach its peak outputs at lower revs.

KrazyKid

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#2187091 25-Feb-2019 21:06

If you own 2 cars and plan to use one mainly for around town commuting a 2nd Hand Nissan Leaf makes a lot of sense.
Can easily fit 2 Adults + 2 teenagers and/or baby seats and has a good sized boot.
Charging at home makes it's very cheap to run.
I only do about 10000 Km a year and am saving at least $1500 a year even after allowing for interest on borrowing extra money (to buy this vs a similar petrol car) and higher depreciation rates.

If this is your only car / a car you plan to use for longer driving trips then it is more of a difficult decision to by an EV. (but can be done)

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#2187120 25-Feb-2019 22:30

note I have not watched these and it's up to you to make up your mind

jamesrt

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#2187251 26-Feb-2019 09:39

Thank-you for all your input.

It sounds like my reservations around the 95 octane turbo are not entirely unjustified, which helps narrow down the selection criteria!

trig42

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#2187257 26-Feb-2019 09:42

What cars are you looking at?

jamesrt

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#2187269 26-Feb-2019 09:54

trig42: What cars are you looking at?

At times, it feels like every car on the planet!

...

We're considering moving into the compact SUV market, so something along the lines of a Mazda CX-3 (which I specifically mention only because I can see the dealer from my work window currently) or the equivalent from another company. And it turns out that there are many, MANY, equivalents.

Also factoring in "can I afford new? (thanks, Mortgage!)", "do I want new, even if I can actually justify it?", "Is it worth considering European even if my understanding is that parts may be harder to get in a few years?"

... and don't even get me started on "What colour is acceptable to the co-driver?"

I need some criteria for dramatically narrowing the list of whats out there; and it seems to me that sticking to 91 petrol engines is a good a way of doing it as anything else. For the first pass, at any rate!

And as much as I'm prepared to accept that a hybrid/electric is a good idea; we do explore the country widely, frequently going into very rural areas, their electric range isn't great, and I'm not convinced that dragging the weight of the batteries along when I'm using petrol is a sound choice either. Not to mention that I was told the other day by someone else doing the research that "most hybrid batteries are not ethically produced".

At this rate, I'll have died of old age or at the very least have re-sat my license again before I can decide...

Coil

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#2187276 26-Feb-2019 09:56

Just avoid a small displacement turbo engine. Under a lot of stress comparatively, turbo makes the need for oil changes a lot more frequent, most new service schedules ignore how a turbo engine should be serviced and I bet you will be up for a new turbo in 2 years. (Hyundai are smart setting a 7500 interval, My mums new golf is set to 15,000KM and it is on its second turbo in 50,000KM)

Let us know what you are wanting to buy, I can offer some advice on what is my preference and why.
Do not get all wound up by the type of petrol the car uses. Check my signature, my BMW costs me 30C per KM and uses 12.5L per 100. This is 98 octane too.

Coil

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#2187279 26-Feb-2019 10:04

At times, it feels like every car on the planet!

...

We're considering moving into the compact SUV market, so something along the lines of a Mazda CX-3 (which I specifically mention only because I can see the dealer from my work window currently) or the equivalent from another company. And it turns out that there are many, MANY, equivalents.

Lots of choice in there. I have heard and seen good things from the CX5, I'd stray from going smaller...

Also factoring in "can I afford new? (thanks, Mortgage!)", "do I want new, even if I can actually justify it?", "Is it worth considering European even if my understanding is that parts may be harder to get in a few years?"

... and don't even get me started on "What colour is acceptable to the co-driver?"

I drove a bright yellow Audi for a year, Colour is not really a thing you can make a decision on unless you are buying new. Buy with your brain not your eyes.
The stigma re Euro cars and their parts is long since gone, if you want to believe that then sure, good on ya but as someone who has had a lot of European cars from many era's I can assure you that the parts are plentiful and cheap. We used to have lunch with the Toyota boys sometimes when i worked for VW parts and we would compare prices and the VW parts for golf's were cheaper then the Toyota Corolla counterparts...

I need some criteria for dramatically narrowing the list of whats out there; and it seems to me that sticking to 91 petrol engines is a good a way of doing it as anything else. For the first pass, at any rate!

In previous reply I said octane type is literally meaningless, do not let this make the decision. The petrol it takes is in relation to a lot of things. Most of the time an engine that takes a higher octane is built to a higher standard and makes more power per liter and that also equals more efficiency, it swings both ways in this area but unless you have a very clear understanding of how octane ratings work and engine then I'd not let yourself get tripped up on this very trivial requirement.

And as much as I'm prepared to accept that a hybrid/electric is a good idea; we do explore the country widely, frequently going into very rural areas, their electric range isn't great, and I'm not convinced that dragging the weight of the batteries along when I'm using petrol is a sound choice either. Not to mention that I was told the other day by someone else doing the research that "most hybrid batteries are not ethically produced".

At this rate, I'll have died of old age or at the very least have re-sat my license again before I can decide...

I'd also avoid Hybrids and electric cars until the technology has gone a lot further.

If I were to offer you some model to look at.

VW Tiguan 2.0 TDI R line from 2013 era.
Subaru forester weird looking things. Good cars from what I can tell, few friends with them and they hold up good. just a terrible multi media interface.
Mazda CX-5.

WyleECoyoteNZ

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#2187281 26-Feb-2019 10:08

Having had two cars from two different manufacturers that produced the same engine power, in two different ways, with the former being naturally aspirated and having a larger engine (1.8) and the latter turbo charged with a smaller engine (1.4), I'd go with the turbo charged car.

Both of these engines have run on 91

Even though both engines produced the same power, the torque figures differed in favor of the turbo charged engine, but not by a lot, only 25nm more in the turbo charged engine

The Turbo charged car is easier to drive, both on the open road on a trip, and around town, just with how and where in the rev band the torque is produced.

At the time of ownership, having had only 1 at a time, the car was the sole family car, and used for everything from family holiday's away to school runs to around town trips. I still currently have the turbo'd car.

With the turbo'd car being the first turbo'd car I've owned would I go back to a Naturally aspirated engine, in short, no.

trig42

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#2187283 26-Feb-2019 10:11

jamesrt:

trig42: What cars are you looking at?

At times, it feels like every car on the planet!

...

We're considering moving into the compact SUV market, so something along the lines of a Mazda CX-3 (which I specifically mention only because I can see the dealer from my work window currently) or the equivalent from another company. And it turns out that there are many, MANY, equivalents.

Also factoring in "can I afford new? (thanks, Mortgage!)", "do I want new, even if I can actually justify it?", "Is it worth considering European even if my understanding is that parts may be harder to get in a few years?"

... and don't even get me started on "What colour is acceptable to the co-driver?"

I need some criteria for dramatically narrowing the list of whats out there; and it seems to me that sticking to 91 petrol engines is a good a way of doing it as anything else. For the first pass, at any rate!

And as much as I'm prepared to accept that a hybrid/electric is a good idea; we do explore the country widely, frequently going into very rural areas, their electric range isn't great, and I'm not convinced that dragging the weight of the batteries along when I'm using petrol is a sound choice either. Not to mention that I was told the other day by someone else doing the research that "most hybrid batteries are not ethically produced".

At this rate, I'll have died of old age or at the very least have re-sat my license again before I can decide...

We just did the same thing, but made the decision pretty quickly.

I was after a small/mid SUV (no need for 7 seats), and something that could tow a small boat up a beach. So was looking for AWD or 4WD.

I quite liked the CX-5, but that got vetoed by the passenger seat driver (she did not like how it looked, I think it looks fine but what would I know?)

We trolled car yards on Anniversary weekend here in Auckland.

Started at Kia, went to Mitsubishi, Nissan, Peugeot (no AWD), Hyundai and Toyota.

Mitsubishi - I'm not that keen on - CVT transmission, and a bit gutless (ASX).

Nissan - salespeople ignored us. Also, CVT puts me off a bit.

Toyota - great cars, quite pricey and not as much candy.

Hyundai - great cars also, good looking, seem to review well, have to pay quite a bit more to get the spec levels/AWD

Kia - great staff, not pushy, wife's preference. Got an ex-demo Sportage in the colour she wanted for just over $32k (1200 on clock, diesel, AWD).

Decision made in about 3 hours, put it on the house, took the bank two days to get the money through. Happy with it. I had also looked at when researching - Suzuki (great 4WD system, car a bit old looking), Seat, Haval, Ford and Holden.

I've now done about 2500km in it - fuel usage is about 7.2L/100km in mixed driving (stop start motorway commutes, plus a couple of out-of-town trips). I get about 800km from a fill - about $85 (plus RUC of course).

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