Thursday, July 18, 2019

Good-looking pressed-steel wheels?

Most often, the aftermarket options catering to those who seek for better-looking wheels are made out of light alloys, and usually either die-cast or forged. Pressed-steel wheels are still usually standard for entry-level models or versions of larger vehicles, but not often so appealing. It did surprise me to see this first-generation Chevrolet Prisma with a pressed-steel wheel that reminded me the Mangels-brand ones which were a popular aftermarket option for trucks and SUVs in my homeland Brazil in the '90s. Sure a small sedan is not the vehicle I would expect to see with a set of those, maybe it was borrowed while a stock wheel was being repaired after getting bent. But anyway, since so many SUVs and small coupé-utility trucklets have high sales volumes, maybe such wheels could've been somewhat appealing to those who either need something more resistent and easier to fix than an alloy wheel or want their brand-new mall-rated SUVs to look tougher...

Tuesday, July 16, 2019

Volkswagen's EA111 1.0L 16-valve turbo, an early, yet failed, approach to downsizing in Brazil

One of the most controversial engines ever, the turbocharged 1.0L version of the EA111 which was only fitted to the Gol and Parati (pictured) between 2000 and 2004 was only available in Brazil. The reason behind its development was the tax bracket that benefits engines up to 1.0L in the local market, which is the only reason it ever became available. In contrast to naturally-aspirated versions of the same engine, either a 2-valves per cylinder SOHC (not available for the Parati) or a 4-valves per cylinder DOHC, the Turbo also featured variable valve timing on the intake. A quite sophisticated engine, it was meant to become somewhat of an indirect replacement to the 1.6L gasoline/petrol version of the EA827 series (the ethanol-powered version remained available as the sole 1.6L engine for the Gol and Parati for a brief period), but ended up rejected by the average buyer of the Gol and Parati range due to its complexity and more demanding oil specifications which were sometimes not observed so strictly by its owners. Rated at 112PS at 5500 RPM and 155Nm at just 2000 RPM, it had a single PS in advantage power-wise to the 2.0L EA827 rated at 111PS at 5250 RPM, which on the other hand still had a higher torque rating of 166Nm at 3000 RPM. And even though the 1.6L EA827 was disfavored on both power and torque with 92PS at 5500 RPM on the gasoline version or 97PS with gasoline and 99PS with ethanol at 5750 RPM on the early flexfuel trim, while the torque ratings were 135Nm at 3000 RPM for the gasoline-only and 136 to 140Nm with either gasoline or ethanol on the flexfuel, the right gear ratio could make such disadvantages less noticeable on normal operating conditions. Plus the fact the 1.6L and 2.0L were in fact cheaper to manufacture, owing much to the SOHC head with just 2 valves per cylinder and the natural aspiration, when the tax advantage for 1.0L engines became narrower around the end of 2002 the Turbo 16V engine started to not make so much sense as it seemed to make at the time of its release, which combined to the reliability records affected at some degree by a lot of maintenance neglect prevented further usage of this engine on other applications. Even the naturally-aspirated version of the 1.0L engine became less sought after by then, with its 69PS at 5750 RPM and 90Nm at 4500 RPM. It's also worth to notice this early approach to the downsizing was performed when direct injection was not so widespread on spark-ignition engines as it is nowadays, so in order to prevent knock it doesn't run so lean as the present-day 1.0TSI does...

Friday, June 21, 2019

Are motorcycles and tricycles any likely to effectively replace a small car for certain users?

In 3rd-world countries, small-displacement motorcycles emerged as a practical tool due to their lower purchase prices and running cost compared to subcompacts, even though they would not deliver the same hauling capacity, not to mention weather protection which is not even an option. Enhancements for cargo capacity available are usually trailers and sidecars, which may lead to some differences in handling and performance but might be cost-effective enough to address some bare necessities.
Their crudeness however, now renders such devices more suitable for cargo hauling. Even the side-car, which used to be widespread in other countries even for passenger carrying before the emergence of the so-called "people's cars", is now mostly used for other purposes. Sure being exposed to weather and elements might not be a desirable feature for the overwhelming majority of car buyers, not to mention the stigmas that surround side-cars not only due to the perception of a motorcycle as somewhat "inferior" but also their usage by the Nazis during World War II.

Even though small cars are widespread on a worldwide basis, with low-cost models such as the Renault Kwid specially developed catering to budget-constrained markets such as Brazil and India, the higher safety requirements and stricter emission rules end up impacting their retail price more than what it does for motorcycles. Sure it's like comparing apples and oranges, but the proposals for an affordable "people's car" that may be rendered either uneffective to address all (or at least most of) the needs of what might be the only motor vehicle available for an entire household. So, the enhanced possibilities of covering much of those needs with a side-car, which may also lend itself to a higher degree of customization in order to serve better to different operators's requirements.

Less stringent emission rules have even allowed entry-level models such as the HaoJue DK 150 and Chopper Road 150 to keep some quite outdated approaches to the mechanic such as retaining the carburettor. Even though EFI has proven its value as a fuel-saving feature, the ease of servicing without overly-sophisticated tools still keeps the carburettor somewhat desirable for some buyers. It may be set to be ultimately phased out on most markets in a few years, but is far from being the only cheaper-yet-effective feature on motorcycle engine tech. Since many of the entry-level ones retain the single-cylinder layout, even air-cooling might be sufficient for most uses, despite the fact it doesn't provide some greater precision on thermal management that could be achieved with liquid-cooling.

Tricycles are also an option to consider, even though their legal status might be subjected to different views on how a motorcycle or similar would be classified. Models fitted with a handlebar and all-open cockpit such as the Can-Am Spyder are clearly more relatable to a motorcycle, while some random Chinese cargo tricycle with more car-like controls might comply to all the same standards applied to a 4-wheeled vehicle of comparable capabilities. Some importers of those Chinese tricycles even have them classified as agricultural machinery in order to circumvent some of those regulations, with the corresponding restrictions applicable to their traffic on public roadways preventing some broader acceptance among the general public.

It's also worth to mention tricycles might provide different degrees of weather protection to operators, and versions meant for either cargo or passenger service are available too. However, the most basic utilitarian ones might not provide the best performance to cover all the needs for private users who could require some more spirited performance and higher range to deal with occasional highway stretches. Despite some modern motorcycle engines being suitable even to a regular compact car, some tricycles such as the ones made by Bajaj in India resort to ancient engine designs with narrower RPM bands which render their power and torque figures less effective under certain circumstances when either a higher-displacement engine or a more rev-happy one could address them more effectively.
Even though some issues that may compromise the chances for a motorcycle or tricycle to become an effective alternative to so many ill-fated "people's car" projects, they may still cover reasonably the needs of many commercial operators. Even for passenger-carrying such as taxi and more recently the apps such as Uber, the easier maneuvering on tighter spaces could turn into a valuable asset, but some regulations concerning the size of vehicles to be allowed as taxi in different cities might lead such option to be not so likely to get widespread so quickly. Arguments such as decreases to emissions and fewer traffic congestions could be presented in favor of tricycles, but in the end might be neglected by regulators and received with fierce criticism from taxi drivers. Well, most of the time even one of those Bajaj tricycles could get the job done as effectively as a conventional taxi from my hometown Porto Alegre, but other factors such as easier resale are also accountable favorably to a sedan such as the Fiat Cronos which may not be seen as a mere bare-bones workhorse that might be eventually perceived as more likely to have been subjected to severe usage and occasional maintenance neglect.

Sure the business opportunities are now less promising for the development of subcompact cars with a small footprint such as the Gurgel BR-800 and Supermini which could serve very similar purposes than a tricycle of a motorcycle with side-car, both a handful of technical issues and the overall perception of the customer regarding subjective factors such as prestige might lead to fewer chances for passenger cars to be as effectively replaced as some small commercial vehicles were.

Wednesday, June 19, 2019

Would a 2-cylinder engine still make sense for the car market?

A feature which used to be found on some of the most interesting small cars from the postwar, such as the Citroën 2CV and the Fiat Nuova 500, a 2-cylinder engine used to be seen as nothing but a cost-cutting measure by most customers, who didn't seem to figure out their practical advantages so well...

The amount of cylinders used to be perceived as a prestige feature, dictating some guidelines to the development of cars such as the original Morris/Austin Mini for which a 4-cyl had to be mounted transversely for space-saving, in order to enable the majority of the floorpan to be devouted for the passengers and luggage, ultimately turning this layout into an industry-standard for small front-wheel drive cars. Most front-engined hatchbacks were following such in the '90s, when Gurgel introduced to the Brazilian market its Supermini resorting to a longitudinal flat-twin engine and rear-wheel drive. In this case, not only fewer cylinders but also their arrangement were relevant for space-saving and to keep a 50-50 weight bias, which would increase towards the rear axle according to the load and improve traction over rough terrain.

Another aspect, most noticeable on flat air-cooled engines, is the cooling efficiency. Taking the example of the VW Beetle with its flat-4 and once again the Citroën 2CV with a flat-twin, the rearmost cylinders of the Beetle would only get cooling air which had previously exchanged heat with the other cylinders, while for a 2CV the cooling flow becomes more homogeneous between the only 2 cylinders. Results may obviously vary among other cylinder layouts, but a twin is still usually better than others when it comes to this aspect.
Considering the success of the Citroën 2CV in Argentina back in the day, which could be perceived as a reason to believe 2-cylinders wouldn't be a taboo there, it's quite surprising to figure out newer models focusing on emerging markets such as the C-Elysée could benefit from such approach, even though very unlikely to be a longitudinally-mounted flat-twin similar to the one which was fitted to the 2CV. It's worth to notice that a 3-cyl 1.2L gasoline-powered engine is available on some countries besides the 1.6L gasoline and Diesel options currently available in Argentina, which may not sum it all but does reinforce the perception that fewer cylinders in a vehicle meant to be somewhat versatile and utilitarian is still acceptable, and maybe such approach is not taken one step further because more sophisticated engines which would increase economics of scale as they're more easily accepted also on vehicles with a supposedly fancier marketing approach.

Considering the widespread perception of engines with fewer cylinders for a given displacement to be less rev-happy, and favoring low-end peak torque over high power throughout a broader RPM band, it's worth to consider not just the impact such matter would cause to overall performance but also the recent trend of downsizing overlapping with some downrevving too. Examples such as the Chevrolet Trax, known in my homeland Brazil as Chevrolet Tracker, show it quite clearly after the 2017 facelift which led to the 1.4L turbocharged engine to replace the previous 1.8L one, both being 4-cyl. Considering the specs for Australia, where both engines are still offered, both are rated at the same 140 horsepower (103 kilowatts), with the naturally-aspirated 1.8L peaking it at 6200 RPM while the 1.4L does the same at 4900 RPM already. Torque rating for the 1.8L is 178Nm (131lb.ft.) at 3800 RPM, while the 1.4L delivers 200Nm (148lb.ft.) between 1850 and 4900 RPM. Sure the turbo is a key factor to the peak torque delivery being flat across a broader revving range, so maybe even a hypothetical 2-cylinder 1.5L based on the ancient Chevrolet 4-cyl "153" engine which used to be a mainstay in Brazil and South Africa could eventually be viable, despite the amount of cylinders remaining seen as a prestige feature in Brazil...

Now looking at Ford, which is having some rough times in Brazil once again, the EcoSport now only has a 4-cyl engine in the Storm 4WD trim, namely the 2.0L Duratec Direct, while other versions are switching from the 4-cyl 1.6L Sigma to the 3-cyl 1.5L Dragon. It's quite hard to compare Brazil and anywhere else, due to the history of automobile industry being totally indissociable from bad political decisions which often led to some unwise strategies among the locally-installed automakers. I'm sure some of the objections raised against the Dragon engine are more biased toward the perception of a 3-cylinder as an impoverishment which is still widespread on the customers' mindset. It's also worth to remind the turbocharged 3-cyl 1.0L EcoBoost which is standard for the US-spec EcoSport is not even available in Brazil, where a fiscal benefit led to this displacement range being more accepted among entry-level car buyers and becoming subjected to some stigma when it comes to other vehicle classes perceived as premium. I know it might sound pointless at first, but this is Brazil, and the SUV trend in a poor country has led even compact models such as the EcoSport to be regarded as somewhat aspirational, and then any step further on downsizing, downrevving or whatever else would become harder to sell despite offering some technical advantage besides a lower manufacturing cost...

Nowadays the model which could be better suited to a selection of 2-cylinder engines in the Ford range is the 3rd-generation Ka, also known in markets such as Mexico and India as Figo. The base engine in Brazil has been the 3-cylinder 1.0L Fox engine since its introduction in 2014, with other options being the 4-cylinder 1.5L Sigma until 2018 when the 3-cylinder 1.5L Dragon replaced it. Even though the model is also available in Europe which is a more developed market, its position as an entry-level econobox could justify an engine which would lead to a lower cost, not to mention the European customer being more open-minded toward fuel savings in this class compared to others who still consider the displacement and amount of cylinders as a matter of prestige. Considering the fewer internal frictions and pumping losses inherent to having fewer cylinders, such approach could eventually become also beneficial regarding the emission regulations in Europe which are getting more and more stringent.

Sometimes a technical approach which had been quite neglected for a while might end up being the best approach to overcome modern challenges, and this happens to apply to 2-cylinder engines. Sure it's not only an objective matter, with more subjective aspects also becoming relevant, but it doesn't justify the absence of such engine layout on most automotive markets nowadays.

Wednesday, March 20, 2019

Quick reflection: are 2-valve cylinder heads in a Diesel engine so outdated at all?

Seeing a Ford Mondeo Mk.4 always gets me thinking about the way a 4-valve per cylinder engine is overrated. Considering the Diesel versions, which were available in 1.6L versions with the DLD-416 engine co-developed with Peugeot either in 16-valve until 2011 or 8-valve afterward, 1.8L with the DLD-418/Duratorq TDCi based on a Ford's own previous Lynx/Endura-D/TDDi engine series always with 8 valves, and the Peugeot 2.0L DW10 and 2.2L DW12 renamed by Ford as ZSD-420 and ZSD-422 always with 16 valves. As surprising as the reduction in the amount of valves might have seemed when it comes to the 1.6L engine, it was not pointless at all. The main reason stated for that switch was emissons-related, as it was implemented when Euro-5 rules became enforced in Europe, with the intake and exhaust porting and the lesser valvetrain inertia benefitting low-end throttle response. Nitrogen oxides emissions, which is the target for the most recent complaints about Diesel engines in general, also decreased due to the restriction on the mass air flow decreasing the internal pressure and aerodynamic heat from compression, thus leading to a condition not so ideal for NOx to form. The lower amount of vaporising latent heat available also reflected on fuel consumption, since a smaller volume of fuel could be injected at each cycle in order to provide a complete combustion.

Tuesday, March 19, 2019

Stretched canvas-top Toyota Bandeirante with 4 doors

There were times when Toyota ruled the 4WD market in Brazil with the Bandeirante, a local derivative of the 40-series Land Cruiser, but not every body configuration available in other countries was offered locally. One of the alternatives to fill this gap was stretching regular canvas-top ones in order to increase its hauling capacity for both passengers and cargo. This modification was mostly performed in Brejo da Madre de Deus, a small town in the countryside of Pernambuco state, with many of the so-called "Toyotão" (Big Toyota) used for intercity shuttle services.
Its role bore some resemblance to the Philippine jeepney based on military surplus Willys Jeeps, but the Toyotão was mostly based on civilian versions and, unlike the jeepney, there were no independent companies developing longer copies of the Bandeirante by their own. Full body enclosure also differentiates it, even though it always relies on canvas roof and doors instead of metallic roofs.

Thursday, February 21, 2019

Hand-operated individual rear brake in a Gurgel X-12

One of the low-volume Brazilian automakers that relied on the Volkswagen air-cooled powerplant when imports were restricted, Gurgel found itself a comfortable position as a manufacturer of SUVs such as the X-12. The lack of a proper 4-wheel drive system required some different approach to increase the off-road capabilities inherent to the weight bias of a rear-engined RWD vehicle. The option regarded as more cost-effective was a manual brake control for each rear wheel in order to emulate the effect of a limited-slip differential and keep most of the torque output to the wheel in contact with a more stable portion of the terrain.
The levers were tied to the parking brake cable of each side, not requiring any rocket-scientist to implement it. The system is not only easier to fit, but also easier to mantain, because even though it might increase the wear on the rear brake liners it's easier to replace a brake shoe than to perform an overhaul in a locker differential.

Saturday, February 02, 2019

Honda CG 150 turned into a cargo tricycle

A month ago I spotted at the Canasvieiras beach in Florianópolis city this '09 Honda CG 150 turned into a cargo tricycle. The conversion was made by the Brazcar company located in Patos de Minas, Minas Gerais state, which previously converted pick-up trucks from regular-cab to dual-cab but switched its business to focus on tricycle conversions for utilitarian purposes. The flatbed fitted to it, however, had a tag from Carrocerias Paraguaçu which is located in Palhoça city, south from Florianópolis.
It's important to remind that light-duty Diesel vehicles are forbidden in Brazil, so such motorcycle conversions became an option for small businesses to use as a cheap and fuel-efficient small hauler which is not meant to be babied, even though this one looked more badly worn-out and neglected than usual. A somewhat surprising feature was the rear disc brake, contrasting to the stock front drum brake.