The Forester’s bigger engine and weight make it more costly to run than the Allex

Hi,

I recently bought a second-hand 2006, turbo-charged, 1990cc Subaru Forester LL Bean edition and have noticed a significant change in my budget on fuel (I initially owned a Toyota Allex 2002 with a 1490cc engine).

I knew the larger engine size would consume a bit more but the disparity is sizeable.

Could it have anything to do with the symmetrical AWD feature in the car.

Noting that I drive mostly on rough roads, does engaging the ECO button have any impact on the vehicle’s stability and traction?

Did you expect the disparity not to be sizeable?

Besides the bigger engine, the Forester is a bigger car.

Couple this with the 4WD transmission (whether symmetrical or not doesn’t really make a difference here) and you have weight gains that will most definitely be reflected on your fuel consumption.

Then there is the aerodynamic profile too… I’ve written about this before, haven’t I?

Hi Baraza,

I buy the Wednesday paper just to read your articles on cars.

I want to point out to you that no matter how well you do, there will be people who always see the half-empty glass.

However, there are certain truths that we should accept, for instance, the fact that most Kenyans drive Toyota saloon cars.

We acknowledge that tastes differ, so what you do is tell readers the situation as it is on Kenyan roads.

I long to read nice terms you used some years back to describe cars.

For example, you described the bonnet of a Toyota NZE as looking as if it had been stung by a bee (I drive an NZE), said some car designers seemed to have worked under the influence of forbidden substances, or that the car would be thirsty and drill a hole in a man’s wallet.

What other expressions did you people enjoy? Any readers out there longing for such terms?

Let’s request Baraza to add more flavour….Mike

Roger that, sir. Beginning 2015 — if I am still here — it will be back to the original “nice terms” that I started off with.

You might have noticed a dearth of car reviews in recent days.

This is because of a certain scarcity of road tests that I can’t really explain.

I fear the era of the motoring journalist might be nearing its end, more so when one learns of new car launches from (other people’s) newspaper articles rather than the PR departments of respective brands.

Nowadays, business editors, lifestyle reporters and unknowledgeable bloggers (people who know diddly-squat about cars) get to sit at the automotive launch table while motoring hacks like yours truly are consigned to staring at pictures of the event on Instagram and asking, “When did that happen?”

The best we can hope for now is a memo from the PR ladies, quickly followed by a phone call confirming whether or not their press release will feature in one column or the other.

The answer is usually no. I find it hard to report on a car I have not driven.

These are subtle hints that we might have reached the end of our usefulness.

The end may be near, but it is not here yet. In the meantime, let us see what we can put together…

Dear Baraza,

I am a computer science lecturer at Chuka University.

I want to start by appreciating the good work you do educating our motorists.

Indeed, information is power and I believe your advice not only helps people make informed decisions regarding cars, but also save lives on our roads.

Keep up the fantastic work!

To my issues:

1. Car fuels: I have noted that whenever I refuel my car at some filling stations, mainly in the suburbs or some highways, its picking or accelerating pace slows down.

When I fuel at Total petrol stations, there is huge difference in performance.

I know you will advise me to be fuelling there but I would like to know the reason for the difference.

What is so special about Shell FuelSave petroleum, which they spend so much advertising, yet I have not noted any difference.

There is a brand of fuel from Shell known as V-Power, what on earth is that? It’s very expensive yet I did not notice any difference in my car. Or is it that my car has a problem?

2. There is a time you indicated that the performance of new Mercedes cars is coming down to about 12km per litre.

I would like to know which specific type and model and how much it costs.

3. Finally, thanks a lot for your article on Peugeot 504s and other ’70 cars and their ever ageing owners.

These guys, some of them professors, I am sorry to say, think that other cars are too useless to be on our roads. I hope they learn to grow with technology.

Another thing: the Nation should not hide your article inside the paper.

I always have to pull out and toss Living magazine aside in order to enjoy your articles without interruption.

Hello Charles,

I would have suggested to the bean counters at Nation Media to do away with Living magazine in your favour but the people who write, edit, print, publish, distribute and sell this Living magazine also have to make a living (see what I did there?).

The magazine also has fans just like Car Clinic does, and I am not going to enter into a contest to see who can spit the furthest, so just grin and bear it.

Anyway, 1. The slow picking/acceleration might be due to the fuel being adulterated and thus suffering erratic combustion properties, or the octane rating is too low so to prevent pinging/detonation, the ECU retards the ignition timing as far back as it possibly can, which in turn affects the revving characteristics and power outputs of the engine.

I have a colleague who has been quietly doing tests on various fuels from various forecourts and his results make for grim reading.

Some stations offer water adulterated with a hint of petrol in it (if you get my drift), others offer muddy sediment and well… our octane ratings are so low, even for the “high-octane fuels”, that what we call premium over here might as well be bathwater for those who know what proper high-octane fuel is.

I’ll see if I can steal those results and make them public.

That Shell FuelSave is like “V Power with added Aromat”, for lack of a better description.

I don’t know what exactly they put in it but Shell claims it improves fuel economy by optimising combustion and thus maximising on the energy transfers that define the four-stroke cycle.

Shell V Power is high-octane fuel (relatively, and I do mean relatively) with cleaning agents in it.

I haven’t tried the FuelSave (with a 1500cc car capable of returning 18km/l on regular driving, I am two steps away from having the consumption figures of an unused bicycle), but I have tried V Power several times and well… I didn’t notice any difference either.

I still use it, though; my engine purrs like new and who knows, it might be the cleansing powers of V Power behind it.

2. Pick any model of Mercedes and if properly driven, it will do 10-12 km/l… yes, even the AMGs. The latest CL65 AMG is a monster of a car, packing a 604hp 6.0 litre twin-turbo V12 engine, but Mercedes say it will do 12 km/l without resorting to desperate tactics.

I guess they mean when shuttling slowly (two miles an hour so everybody sees you) from the driveways of well-off people to the driveways of other well-off people.

Bring that AMG to the Kiamburing Time Trial and 12km/l will be something that you only read about in the brochures of plebeian vehicle models.

3. You are most welcome. When I err…. “slandered” the 504 (somewhat, I once had a Peugeot too), a reader was disappointed and asked me to try again, this time with a Volkswagen Type 2 bus and I was not kind to it either.

Now the VW Owners Club might have put out a contract on my head, if rumours are to be believed.

That aside, classic cars are an acquired taste and provide joy to some (mostly grease monkeys) while at the same time suffer derision from the PlayStation generation.

If I spot a well-kept Peugeot 404, I’d nod quietly to myself and be glad that there exists a motoring enthusiast out there with passion for the past.

Those who found more than one TV station on air at birth will look at it and ask why it is so slow, where the air-conditioning is and how come there is no letter at the end of the registration number.

Dear Baraza,

1.  Internal combustion engines give off lots of heat. Considerable effort and resources are actually spent cooling them.

Cooling systems take up space and make the cars heavier, etc. It seems to me there are lots of inefficiencies here.

It appears that it would make sense to somehow convert more of that heat energy to boost the propulsion of the vehicle instead of concentrating on just refining ways of losing the said heat to the environment.

To your knowledge and in your estimation, has there been exhaustive research in this area?

2.  The average car is equipped with a 12-volt battery and a generator (alternator).

Noting that for most cars I know, the alternator is always working, I expect that, as a result, it produces much more electricity than the car will ever require.

Does this not lend some credence to the concept of “hybrids’”, perhaps even the “loathsome” Prius?

Jeijii

1. Yes, the internal combustion engine is a paragon of inefficiency, barely cracking 40 per cent.

This is just about as far as it will go, for the engine itself.

Further losses occur in the transmission and drivetrain, which is why one type of hybrid involves the use of the engine as a generator rather than a source of tractive power.

There are fewer losses that way.

The heat dissipated from the engine is primarily a result of friction, and more often than not, this heat is radiated away from exposed parts, absorbed by convection where the cooling system can reach, and dissipated by conduction where heat shields are attached.

Your theorem sounds attractive: instead of wasting this heat, could it not be put to good use? Well, a) some of it does get put to good use, such as in declogging the catalytic convertor/diesel particulate filter (DPF) and in warming up the interior of the car b) there is one small problem, and that is how to trap this heat.

Of all energy forms, heat is the most dynamic and the most easily lost.

You will have to do a lot of capturing if you are to acquire any useable energy from heat, and while doing this capturing, some of it will be escaping.

Then where will you store this heat as you wait for it to accumulate to useful levels?

Lastly, heat being very dynamic, is more often than not the last form of energy before dissipation: it is easy to convert other energy forms into heat, but the reverse is not necessarily true without involving elaborate equipment.

Where will this equipment be stored?

Won’t you be making the car even heavier and more complicated?

Most of the research has been focused on minimising heat losses rather than trapping the heat itself.

Petrol inside your tank is chemical energy. When oxidised (combustion), it explodes, which means this chemical energy has now been transformed into various other energy forms: light energy (the flash of the explosion), sound energy (the “boom” of the explosion) and heat energy.

Light and sound are mostly wasted, though, through sound deadening and the use of non-reverberating materials, the sound waves can fail to be absorbed and become kinetic energy.

The heat energy is what is desired here; it causes a rapid expansion of air, and this rapid expansion results in motion of air particles: kinetic energy.

The kinetic energy of air molecules is then transferred by impact to the piston crown, and this energy forces the piston downwards and from here I think you know the rest… the end result is the engine rotates and eventually the vehicle moves.

The cooling system is designed to do away with heat from friction, and this heat can get to very high levels owing to piston speeds (in high performance engines like the E46 BMW M3’s, piston speeds can reach up to 87ft/s, which is quite high)

2. When you run out of fuel in your ordinary car, the car will not run on the battery, will it?

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