Is your ‘mtumba’ in the right Kenyan form?

Last year I advised you on how to buy a second-hand car. The article covered all used vehicles, be they reconditioned or otherwise. When the economy was liberalised back in 1992, it opened the floodgates for reconditioned ex-Japan, ex-UK, ex-Singapore, and ex-Dubai cars to make their way into new hands for a lot less money than buying a brand new, locally franchised unit.

Light was at the end of the tunnel, for the buyer at least, because most franchises saw a massive downturn in new vehicle sales. The question remains, is there real wisdom in buying a car that has been in use elsewhere, a place very different from here? Because the cars that run there, despite the fact that they look similar to the ones running here, are vastly different in very many ways, right down to the paintwork.

We live in the tropics, while UK, Japan and Singapore lie outside the tropics, or towards the outer edges. Our weather patterns are different, as are our climates. The level of economic development also differs: you cannot compare Dubai’s infrastructure to ours. As such, their roads are different, as is the type of fuel they are supplied with by oil giants like Shell and BP.

This means their cars are built to certain specifications: their engines are built to operate within certain atmospheric conditions while burning certain types of fuel, their suspensions have been set up to withstand certain road conditions, and, yes, even the paint has been applied with a certain intensity of sunlight in mind.

What happens above Cancer and below Capricorn climatically is not the same as what happens within the two tropics. Let us start with the weather/climate and its effect on engine design.

Countries like Japan and UK, from which we get a good number of cars, experience snowy winters, with temperatures dropping below 0°C, so their cars have to be made with extreme cold starts in mind. Our worst winter, if you could call it that, goes as far as fog appearing where it normally shouldn’t, with temperatures dipping to 6°C in very extreme cases. Out there, 6°C is the norm.

As such, most cars from these regions come with the radiator filled with some ferruginous stuff that resembles premium petrol somewhat, or what we like to call super. It is red in colour. The source of the rusty tinge is the presence of an anti-freeze additive that prevents the water in the radiator from freezing during inclement weather.

Nobody wants ice in their radiator, especially when facts like the anomalous expansion of water comes to mind: water, unlike other compounds and elements, expands when freezing, during the formation of ice.

Break your radiator

That ice could break your radiator or, even worse, crack your engine block if allowed to form. The antifreeze lowers the freezing point of that water to a level so low that the temperature range where it can now freeze is beyond reason. Our weather rarely, if ever, gets to freezing, so that is one property we do not need.

But do not rush to drain your radiator claiming “I don’t need this stuff, water will do”. You still need the anti-freeze. Not only does it make water hard to chill, it also has some anti-rust and anti-deposition properties. The liquid prevents the radiator and other iron-based channels that it goes through from rusting (iron + water = rust; this is chemistry that even the uneducated can claim knowledge of), and these channels include the water jackets around the engine block.

It also prevents minerals in the water from depositing themselves and clogging up those channels with their scum, similar to what eating bad cholesterol does to your blood vessels, or from reacting with the metal components in the automobile’s cooling system.

Sticking with the engine, there is the small matter of fuel grade. Developed countries run some fine lead-free high octane petrol (98 RON) and sulphur-less diesel. The jungle juice that we pour expensively into our tanks around here has a lower octane rating (92 RON), which means some high performance cars, particularly the turbo-charged versions, will not last long locally. Ask a man who owns a Mitsubishi Lancer Evolution car (Evo VII or earlier) what this means. It is only within the last decade that we switched to lead-free petrol and low-sulphur diesel.

Fuel jetting, the means by which petrol/diesel is sprayed into the cylinders, also differs slightly. Our warm weather means that the petrol in our tanks is less viscous than what the Brits experience during snow conditions. As such, the two different viscosities dictate that the fuel will not flow through the injectors at the same rate, or be vaporised at the same rate either.

Suspension settings are also made with predominant driving surfaces in mind. Belgian pavé requires soft, pliant suspensions, while mirror-smooth tarmac/cement could be handled with a slightly stiffer setting without necessitating a trip to the chiropractor.

Adjusting a first-world car’s setup to handle third world conditions is called tropicalisation, and it usually involves making the following changes:

Cooling system: This is mostly left untouched, though the thermostat in the engine bay could be set to activate the fans/water pumps at a lower temperature than that for abroad, seeing that we do not need a long warming up period after cold starts, and our warm weather means our engines heat up faster in use than in cold weather.

A word of advice: when warming up your car in the morning, leaving the engine idling with the car stationary is not the best way to warm up, but at least it is better than revving the nuts off your car hoping to reach critical temperature faster. You will warm the engine faster like this, yes, but you are also ruining it because the oil/lubricant has not had a chance to circulate properly and thus smooth off the high-friction circumstances associated with high engine speeds.

The best way to warm up your car would be to take off immediately after starting, keeping engine speed low (limit yourself to about 1800 rpm in a petrol engine car and 1200-1500 rpm in a diesel passenger car: we are speaking of diesels that are below 4.0 litre capacity and rev to 4500 rpm max. Heavy commercial diesels should be operated below 1300 rpm)

This technique warms your engine faster, as well as warming up your transmission fluid, spreading the grease in the ball, universal and CV joints and warming up the tyres, thereby optimising the overall performance of your car. More on this later.

Engine: This is the one area that receives the most attention when tropicalising a car. Sometimes cylinder heads have to be replaced, thus changing the compression ratio of the car (lowering the compression ratio allows a car to run on “dirtier”, low-octane stuff).

Turbo-charged cars are all the more sensitive to the compression ratio adjustment due to the risk of pre-ignition and emissions control. The high temperatures associated with turbo applications easily cause pre-ignition, a situation where the fuel ignites before its exact moment is due.

The hot, compressed air from the turbocharger causes this (Charles’ Law from Form One Chemistry). To counter this problem, turbo-charged cars tend to deploy a bit more fuel from the injectors, to create a “wetter” intake charge (air-fuel mixture) that will not be easily lit up by the high temperatures of the forced induction.

The downside of this is the vehicle has more emissions per kilometre than a naturally aspirated one, due to the richer mixture being burnt.

Running a high-performance turbo engine (like the Evo cars) on low octane fuel causes even more complications: now the fuel won’t even burn fast enough in the engine and sometimes catches fire in the exhaust pipes while under power (and thus high engine revs). This is when a car is said to have a “miss”, characterised by a loud report, not unlike that of a non-repeating firearm, from the car’s exhaust.

The best way out of this kind of fix is to change the compression ratio, thus limiting the car’s ultimate power figures and lowering the rev ceiling to allow for more efficient combustion.

Along with replacing the cylinder heads comes re-mapping of the car’s ECU, what people call the computer box. The chip is flashed, or re-programmed to change things like the valve timing (variable) and fuel injection, thus catering for lower quality fuel. Valve lag and valve lead are changed to create an Atkin’s cycle-like situation where there is a short intake stroke, with long compression and power strokes. This lowers an engine’s overall abilities but ultimately allows it to run on porridge… almost.

Fuel injection is also changed to change the spray angle, the injection periods, and injection times to compensate for the low octane fuel’s slower burning characteristics. Some changes might also involve the fuel filter, fitting a coarser one, but this is not common.

Some manufacturers go about tropicalising an engine in a funny way. When they come up with a more advanced (and thus more sensitive) engine for a new car but lack the infrastructure to support their new technology in the third world (mostly), what they do is sell their new model with the old engine instead of the improved unit. The existing material should cater for those “old” compost-burning engines as they have been, and in most cases the customer would be none the wiser.

Others, like Peugeot, simply continue selling an out-dated, obsolete product long after it goes out of production in the rest of the world. The 504, for instance, was killed off in the early ’80s worldwide, but production continued in Kenya and Nigeria (only two countries) until 2004.

Exhaust system: this is no longer a problem, but before we had unleaded fuel, importing a car with a catalytic converter and feeding it petrol laden with the heavy metal fouled up the cat, clogging it and increased the back pressure from the exhaust system to the engine, thus impeding its performance. Now that we have unleaded, this is not too much of an issue.

In the olden days, this problem was solved by simply removing the cat, but this is very illegal in some countries and harmful to the environment. The cat may also be fitted inside the exhaust back-box, which houses the silencer, so chucking it will make your car noisy (and here comes NEMA with their own interpretation of existing noise laws….)

Suspension: Let’s not pretend, up until recently, ours were not roads and highways to brag to anyone about. Poor finish, cliff-like edges and pot-holes that could swallow an entire Vitz characterised our national roadway grid, and you needed a car with tough suspension if you planned to own and drive it longer than a few weeks.

Foreign cars have slightly stiffer, lower-riding suspension systems, complete with low-profile tyres to improve their handling without compromising too much on comfort… their roads are good, so even a car with a suspension set on bed-rock, Fred Flintstone-style, will not break your back. The suspension components are also made from lighter material to reduce unsprung weight and improve steering response and overall handling.

You try that here and your car will fall to pieces before you get through your third tankful of refined crude. Even with the improved (and still improving) road network, we still have sleeping policemen and rumble strips that could shatter your dental formula if engaged at speed. Sleeping policemen, by the way, are not the boys in blue snoozing; they are those fat, elongated bumps that don’t seem too bad, until you hit one at speed and ruin your car completely, after which you treat them with a little more respect.

Cars meant for use in the harsh realities of the third world (and Australia) need heavy-duty suspensions, made from robust material to withstand the incessant pounding that come with driving over cheap-skate road surfaces. They also need to be set more pliable, with more travel, to increase the comfort level as you navigate through highway hell.

Ground clearance

Some cars have the ride height increased, to add to the ground clearance and thus allow the car to go over said speed humps and/or small rocks in your path. Low profile tyres are also given a wide berth: the fatter rubber/air mattress that is the tyre wall accords improved comfort and shock-absorbing when driving rough.

Stiff settings, low ride height, low profile tyres and lightweight suspension materials are for performance driving anyway, which you cannot do when the road won’t allow, so we don’t need them.

Adjusting the ride height, by the way, comes with widening the track to maintain stability which might have been sacrificed when making the car stand taller. Adding spacers between your mountings and the suspension components will just destabilise your car, a fact that you will discover when on two wheels through a corner and your passengers are cursing you in one last desperate breath before they die. Leave the ride height adjustments to the experts, or manufacturer.

Paint: There is not much you can do about this except giving your car a new coat. Those flashy, pearlescent “wet” jobs that come with luxury models (especially Lexus) are meant for places where the sun does not burn too hard.

Expose that fancy art to the equatorial sunshine and watch it degenerate into some matte, multi-shaded amalgam of ugliness; either that or it forms some unsightly pustules just beneath the surface that eventually burst, cracking the paint or even peeling it. Cars sold in such sunny places have their own available paint schemes that can withstand this kind of exposure, which means certain colours or shades available elsewhere cannot be sold locally.

We are not through yet. Brace yourself, because next we discuss the socio-economic impact of the mtumba market, and if it has reached the end of its usefulness, or if the local franchise holders should get with the programme and open up their own grey import channel.



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