Volkswagen and some attempts to get rid of naturally-aspirated engines since 2003: why the Virtus is an example of turbocharging being far from one-size-fits-all?

The introduction of a facelift for the Volkswagen Virtus in Brazil for the 2023 model-year, along with the phaseout of the 1.6 MSI engine in a gasoline-powered trim for regional exports and flexfuel for the local Brazilian market, could fool some people to believe a turbocharged 1.0 or 1.4 TSI to be suitable for every customer. Odd enough, in India where the facelift was avant-premiered worldwide at the local introduction of the Virtus which was more recent compared to Brazil, the Virtus was always fitted with either the 1.0 or 1.5 TSI engines, yet the 1.6 MSI remains available as an export-only option. Countries such as Mexico, which switched from the Brazilian Virtus to its Indian counterpart, are more favorable to naturally-aspirated engines with a larger displacement, even though the turbocharger could be seen as a good addition because it may also provide some compensation to the effects of a quite extremely high altitude in Mexico City for instance. Other aspects which may be also worth to remind are the resort to port-injection in the naturally-aspirated 1.6 MSI engine, simpler than the direct injection fitted to TSI engines and easier to convert to some alternate fuels such as compressed natural gas (CNG) which is quite popular in Argentina, Bolivia, and Brazil.

The presence of a turbocharger might not be a maintenance nightmare at all, yet it does have its fair share of complexity due to the high temperatures a turbocharger tends to operate and how it may require a stricter observance of the minimum specifications for motor oil. Sure using a lower-grade oil in a modern naturally-aspirated engine may not be a good recommendation at all, and neither adapting a carburettor instead of the electronic fuel injection like it often happens in Argentina as the do-it-yourself culture is still quite common there and inviting to some makeshift, even though it may lead to other electronic systems to fail considering the greater integration between the engine management system, some accessories, and safety devices such as ABS brakes and traction and stability controls. It's also worth to notice in some countries the Virtus was introduced only with manual transmission and the 1.6 MSI engine, such as South Africa where it's sourced from India and named Polo Sedan instead, and its powertrain contrasts with the all-turbo lineup and the availability of the DSG transmission for the South African Polo hatchback.

What would be the most challenging aspect to modernize a 2-stroke engine?

The most highlighted 2-stroke gasoline-powered car engines in Brazil were fitted to the DKW-Vemag range, made under a license from the same Auto Union which would later be reorganized as the modern iteration of Audi, with the brand changing from DKW to Audi reflecting exactly a switch from ancient 2-stroke to 4-stroke engines which were perceived as state-of-the-art in mid to late-'60s. Littie could'be been tried in order to make the DKW 3-cylinder 2-stroke 1.0L engine better suited to a more prestigious aspiration such as in the DKW-Vemag Fissore, even though the Lubrimat system resorting to a separate oil reservoir instead of requiring a fuel and oil premix noticeably decreased both smoke and spark-plug fouling under certain engine loads, and could be effectively more practical than having to change the oil in a 4-stroke engine periodically, even though the total-loss oiling would not be much suitable to forced induction through a turbocharger, and even if a belt-driven supercharger could be implemented it would need its separate splash-lube oil system. Back in a day when electronic fuel injection sounded more like sci-fi, and mechanical fuel injection was much easier to justify for Diesel engines due to a much higher complexity compared to carburettors, the fate of 2-stroke engines in cars was sealed...

Besides the automatic lubricating system through oil injection, which would later also become popular in 2-stroke motorcycles, other developments started to emerge in the '70s when an "outdated" 2-stroke car was turned more into a technical curiosity in Western countries and more efforts were directed to the evolution of 4-stroke engines. Just like intake reed-valves and exhaust power-valve systems which were fitted to some 2-stroke motorcycles eventually provides an effect comparable to what a 4-stroke engine would get with a variable valve timing, it's worth to notice the differences between the intake flows in a 2-stroke engine posed additional challenges for electronic fuel injections to become effective regarding fuel economy, with both direct injection at some earlier stages and more recently transfer-port injection being implemented to certain 2-stroke motorcycles, all while the economics of scale are more difficult than a port-injection setup in a 4-stroke. So, besides cost and economics of scale favoring 4-strokes, an increased hardship to adjust either a direct injection or a transfer-port injection to inject a fuel in liquid phase such as gasoline or ethanol as well as certain alternate fuels such as CNG or Hydrogen in vapour phase might have become the most challenging aspect for any attempt to rehab 2-stroke engines in cars.

The Fiat Pulse makes downsizing seem rather pointless

One of those Fiats developed more specifically to the Brazilian market, the Pulse was released with the GSE/Firefly engine, always in flexfuel trim for Brazil and gasoline-powered for regional export, with a 4-cyl naturally-aspirated 1.3L version as the entry-level engine (and only one available in Mexico) with either a 5-speed manual transmission or a CVT automatic and the 3-cyl turbocharged 1.0L MultiAir III only with a CVT. Later a sporty Abarth trim with a MultiAir III version of the 4-cyl 1.3L was added, with a more conventional 6-speed automatic, but the rather specific profile of a sporty model might not be so unjustifiable for turbocharging. However, for the regular trims, the naturally-aspirated 1.3L ended up with a better fuel-efficiency, even though the 1.0L turbocharged was supposed to be much better and technically superior, with its direct injection rendering unnecessary as a knock-suppression measure an excessive enrichment of the air-fuel ratio under boost which used to be more usual when port-injection was the rule even for turbocharged engines. Sure the 56.25% higher torque rating for the 1.0L MultiAir III might be appealing, not to mention the turbocharged provides some altitude compensation once the turbo-lag is over while the naturally-aspirated engines suffer from a more acute performance decrease on extreme altitudes, and considering FIA racing homologation rules the turbocharged engine with a 25% lower displacement would actually be supposed to equate to a naturally-aspirated engine 27.6% larger in displacement than the one fitted to the Pulse, which technically is quite impressive, but the turbocharged engine ends up not only having a higher fuel consumption but also costs more to make and mantain. It's also worth to notice that some operators such as taxi drivers may also consider to upfit the vehicles with a Compressed Natural Gas alternate fuel setup, to which the port-injection of the 1.3L naturally-aspirated engine is still better suited.

Tricycle with a food-truck body in my hometown Porto Alegre

Among those vehicles that may look too odd from a 1st-world perspective, sure this Chinese-made trike would be highlighted. More often featured with a flat-tray made out of sheetmetal or a cargo box made out of fiberglass, this one was fitted as a stand to be used as a mobile food stand. The engine is a 200cc water-cooled single-cylinder, modified from those random copies of the Honda CG 125 so widespread among Chinese motorcycle manufacturers, It resorts to an auxiliary reverse gear which in theory can be used with all the 5 forward gears, and a driveshaft, so no chains to adjust once in a while. Its rear roof is raised when stationed, enabling the operator to stand while handling something inside, and a window on the right side enables the vendor to serve customers on the curbside, usually to the right in a right-hand traffic country such as Brazil.

Brazilian replica of the Porsche 356 Speedster

It's not so uncommon to see replicas of the Porsche 356 Speedster in Brazil, most locally-made with a fiberglass body and based either on a dedicated tube-frame for newer ones or on the floorpan of some early Volkswagen.

This one is fairly recent, made by a company named FerCar and better known by its beach-buggies.

Quite accurate, yet those headlamps gave me a clue that it was more likely to be a replica.

'67 Triumph Spitfire Mk.III hardtop

Definitely unusual to see such a beauty in my hometown, but it's undeniably eye-catching. This might be the first Triumph Spitfire that I have ever spotted on the wild.

Well, maybe the most surprising aspect is the stock engine still being under that hood, instead of having been replaced by a Chevette engine which used to be a fairly common adaptation to small British cars in Brazil...

2004 Suzuki GN 125 styled as a bobber

A model which sold quite well in Brazil from 2002 to 2017, the Suzuki GN 125 is still quite common to see either stock or modified to different extents. Having become some sort of cheap option for the folks who would otherwise get a Harley-Davidson, it's easy to see many with modifications inspired by some of the most traditional styles enjoyed by the Harley-Davidson owners and enthusiasts. This 2004 turned into a bobber is a good example of how the Suzuki GN 125 became popular for what could be seen as a makeshift Harley-Davidson lookalike...

Having been rebadged in Brazil as Suzuki Intruder 125, there is a minor cult-following to this model in the local market, as one of the few "affordable" cruiser-inspired motorcycles with a reasonable support both by the local representative of Suzuki back in the day and mostly by the aftermarket now, unlike so many Korean and more recently Chinese copies of some ancient Hondas which faded away as fast as they appeared. And even though its performance might not seem like the most exciting for the highway, it's undeniable the Suzuki GN 125 was quite well suited to the bobber styling.

Chevrolet-based Santa Matilde SM4.1 convertible

One of those Brazilian cars made during the times when imports were prohibitively restricted, and one of the few not resorting to a Volkswagen-based powertrain, the Santa Matilde SM4.1 had the Chevrolet 250cu.in. straight-six as the standard powertrain available both in gasoline and ethanol versions, and a much rare turbocharged version with the 151cu.in Chevrolet 4-cyl engine derived from the very same basic project of the straight-six, with the turbocharging implemented by Santa Matilde and avaliable only in an ethanol-powered setup. This convertible is of the 1987 model-year, fitted with the normal Chevrolet straight-six engine in the gasser version, and a manual transmission.

Odd location of the fuel tank well visible in an Argentinian GMT400 Chevrolet Silverado

In contrast to the USDM GMT400 Silverado, which had a saddle-mounted fuel tank and left-hand filler cap in the front quarter of the pick-up box as a standard fitment, the Argentinian and Brazilian ones had a right-hand filler cap in the rear quarter. In order to save on tooling and reuse much of the parts for the previous generation of the C/K trucks which had already been made in Brazil and Argentina, the tank in the rear overhang was much easier to implement.

Communicating-vessel fuel indicator in a Harley-Davidson Sportster

Spotting a Harley-Davidson motorcycle is quite usual in my hometown, and they usually are fitted with some aftermarket accessories. One which has caught my attention was this 2005 Sportster 883, adapted with a communicating vessel to serve as a fuel gauge.

Proper fuel gauges in Sportsters were something I never seen so often, let alone in a carburettor-fed one such as this. Even though this setup has the advantage of not requiring any electrical wiring, unlike the fuel gauge kits often found as aftermarket units, I'm not so sure if a similar setup would be legal for use in other vehicles.