Tuesday, January 17, 2012

Ancient cars: a real threat to the environment?

 Old cars, like the Volkswagen Karmann-Ghia, are capable to awake passions even after decades out of the production lines. Not just due to the design cues, the old-school rides also delight enthusiasts all around the world. However, emission and safety laws often make them be seen just as a piece of junk despite all the historic value and even some technical advantages over current options on the market...
The Karmann-Ghia itself, for example, doesn't require cooling fluid for its rear-mounted air-cooled engine, avoiding potential risks of an incorrect disposal of it. Also, since it's carburettor-fed is easier to perform emergency repairs at the roadside while in a modern average plastic ball car with electronic fuel injection a computer is often demanded to be connected to the engine.

Despite all that environmental speech claiming newer vehicles as "more fuel-efficient than old beaters", it does worth to remember that some old engines such as the GM "Iron Duke" 4-banger with a 2-bbl carburettor can make an old Chevrolet Opala from Brazil or a South-African Chevrolet Ranger get a mileage close to new models in a comparable size, often with an engine displacement below its 2.5L.
And since its RPM range is not so broad, the torque distribution at a lower revving is already well modulated even without modern tricks like the variable valve timing.

A carburettor also has a smaller impact in the environment when disposed than a complete EFI setup with all its wiring and electronic modules, being easier to recycle with low technical resources.
And even repairs or preventive maintenance are simpler, cheaper and can even be performed at home with simple tools. No wonder the Toyota Corolla still relied on carburettors for its entry-level versions in the Philippines until late 90's, for example...

Another trend that is now outdated in the automotive market are the 2-stroke engines, that are still remembered in models like the DKW F-91, known in Brazil as DKW-Vemag Belcar.
Due to the old 2-stroke oils from its time, often the engine is reported to release a dark-colored smoke, but this issue has been addressed by current synthetic oils that have becoming popular among off-road motorcycle riders or even the vegetable-based ones used in kart racing. Also, since the oil is burnt alongside the fuel, it avoids unproper disposal of old motor oil that can lead to water and soil contamination...

Another point of interest is the ability to run on alternative fuels in older vehicles: while the electronic engine management features were already available when models like the Chevrolet Lumina APV/Pontiac Trans Sport/Oldsmobile Silhouette started to hit the American market as FFV's (FlexFuel Vehicle) in 1992, the Ford Model T had a special carburettor with a variable diffuser since 1908.
OK, the manual ignition advance control helped to deal with the flame propagation speed issue using different fuels like ethanol, gasoline or kerosene. Even gaseous fuels such as CNG/biomethane could be used without all those electronic auxiliary modules from aftermarket conversion kits to fool the electronic control management in modern engines...

 As far as ethanol goes, it does worth to remember again the Volkswagen air-cooled engine: from early 80's until 2005, it had some dedicated-ethanol versions available in the Brazilian market. An used cars dealer from Pelotas city, near the Uruguayan border, once told me that he had a dedicated-ethanol Beetle, but due to an innacurate thermostatically-controlled airflow restriction device around its heads and cooling fan he often used gasoline in the winter to get the idling more stable. But, despite some beliefs that an air-cooled engine is harder to convert to run on alternative fuels due to the less accurate temperature control, it's not impossible.

Other engines often portrayed as a danger to the environment are the diesels, most notably the older ones with an all-mechanical injection setup. The particulate matter emissions issue has been addressed in newer vehicles with the electronic injection management and particulate filters, but actually even an old diesel with a correct tune at its injection pump won't generate an outrageous amount of soot...

It's also not so unusual for an older diesel-powered car to have a higher fuel-efficiency than a comparable gasoline-electric hybrid. Also, the compression ignition works better with liquid alternative fuels such as ethanol and biodiesel, while the inability to operate with gaseous fuels that require a spark ignition is not really so intense if we consider the trend in the current hybrids that is a workaround on the camshaft to hold the intake valve timing for a longer period to simulate a power stroke longer than the compression stroke, like happens in an Atkinson-cycle engine.
And the traction batteries of a hybrid are filled with some dangerous chemical compounds...

It does also worth to remember that some older vehicles demanded a smaller amount of raw materials than its recent counterparts to be made of, such as the 1st-gen Volkswagen Transporter, known in Brazil as Kombi and remaining on production. Its external size is actually closer to the minivans, but it can often face some modern opponents in an upper size class without too many disadvantages...

 Another thing to consider is the comfort: some older models like the classic Jaguar XJ-series still have an outstanding setup that actually doesn't owe too much to its newer counterparts such as the smaller Jaguar XF.
Okay, some newer amenities and gadgets are cool, but are'em really necessary in a car??? Actually no...

So, despite some different opinions, an old beater can even have a lower environmental impact than a brand-new vehicle...

3 comments:

  1. Older mechanical-injection diesels are great, and not so bad as often shown. Some people complain about excessive smoke while driving uphill, but there are injection pumps fitted with an altitude compensator pin to get the air/fuel mix leaner automatically, all without any electronic interference.

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  2. Jonathan ChristianssenMarch 12, 2012 at 1:58 PM

    Actually even some earlier electronic fuel injection systems were not so complicated to mess with, then easier to replace damaged parts. My mother used to have an Opel Corsa B with a single-point fuel injection, nearly an electronic carburator, still not so easy to work around like my grandpa's Chevrolet Ranger but not too complex like the current models of the Opel Corsa D with its multi-point fuel injection and the electronic ignition. Mechanical or analogic electric systems are always easier to work on, but electronics are just unpredictable.

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  3. A cousin of mine who lives in Apalit, in the Philippine province of Pampanga, owns a widebody Corolla just like this one from the pictures, but with unpainted bumpers, mirror caps and door handles, no power features (steering, locks, whatever) and no aircon, it's a '96 XL base model with the 1.3 carb'ed engine. Think about a no-frills vehicle, well, at least it's nearly unbreakable but when something goes not as it would be supposed to be it's easy to fix with simple tools. Too bad there's no carburator in brand-new cars anymore, blame it on the dumb EPA mandate in the United States. I had to go to Florida where the smog patrol is not so severe as in California to have my '04 Corolla repowered, had it fitted with a 2C JDM Diesel but due to the electronic controls at the slushbox it's now gone to leave room for a stickshift. At a first moment I wanted to get a carb'ed engine but the best non-electronic one at the time was that Diesel and since it's not so bad in performance while coped with the stickshift and there are not even spark plugs to care about it's great. I'm even having close mileages than a neighbor has with his problematic Prius...

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