2019 Dodge Challenger R/T Scat Pack 1320Peter Bleakney / Driving Theres nothing quite like horsepower until you dont have any. A recent test of the European Skoda Fabia S hatchback and its diminutive 1.0-litre three-cylinder engine drove the point home.With just 59 horsepower and 70 foot-pounds of torque, it could barely move the front bumper, never mind the rest of the car and its driver the 16.4-second run from zero to 100 km/h proved it to be the epitome of slow.Thats definitely not the case with these five horsepower leaders, all priced under $50,000 (based on the MSRP before manufacturer discounts). All five are charismatic rides with the ability to wow the driver and rider alike!2020 Ford Mustang GT$87.58 per horsepowerLeading the way is the Ford Mustang GT Fastback. The 5.0-litre V8 develops 460 hp and 420 lb.-ft. of torque and drives the rear wheels through a six-speed manual gearbox that rev-matches on downshifts.It also comes with some fancy drag-inspired technologies. It has a launch control system and a line-lock setup. The latter allows the front brakes to grab the rotors, but leave the rear brakes off, so doing a burn-out to warm the rubber is as easy as it gets.The GT is also very nicely balanced. It is comfortable on an everyday basis, yet body roll is controlled and the tires let the driver know when they are reaching the traction limit. Punch the gas at this point and the back end breaks away in a controlled manner that is easily caught. The adjustable steering also lets the driver pick the right weight.The numbers? With a base MSRP of $40,289, it costs just $87.58 for each of the 460 stallions. It runs from rest to 100 km/h in 4.2 seconds; does the more important 80-to-120-km/h passing move in 2.4 seconds; and it has a quarter-mile time of 12.2 seconds. The posted average fuel economy, not that it matters, is 13.3 litres per 100 kilometres.2019 Chevrolet Camaro 1SS$97.20 per horsepowerThe 2019 Chevrolet Camaro has new front and rear fascias along with some tweaks to the equipment list. The sleeper in the lineup is the Camaro 1SS it is a true wolf of a ride that never fails to entertain. In this case, the 1SS arrives with a 6.2-litre V8 that fires 455 hp and 455 lb.-ft. of torque through a six-speed manual transmission with rev-matching downshifts.It also gets 20-inch wheels wearing 245/40 front and 275/35 rear tires; four-piston Brembo brakes; and a performance suspension, along with a limited-slip rear differential. Track Mode puts everything into hyper, including the exhaust note. The serious punter will add the 1LE Track Performance package. It is not cheap at $8,495, but it gets bigger six-piston front Brembo brakes, a magnetic ride control suspension and Recaro bucket seats, among other things, all of which make a massive difference for the track aficionado. The Camaro is not quite as forgiving as the Mustang when the back end lets go the traction is prodigious, but when the tail disappears, it takes fast hands to catch things.With a base price of $44,245, each of the Camaro 1SSs horsepower cost $97.20. It runs to 100 km/h in 4.2 seconds; does the 80-to-120 km/h passing move in 2.5 seconds; and has a quarter-mile time of 12.4 seconds. The posted average fuel economy is 12.6 L/100 km.2020 Dodge Challenger R/T$106.82 per horsepowerWhile the Dodge Challenger and Charger are essentially the same, it is the two-door model thats the focus here. This year, the 840-hp Demon goes away, but the 797-hp SRT Hellcat Redeye joins the lineup. Anyway, back to the real world!The Challenger R/T arrives with a 5.7-litre Hemi V8 that pushes 372 hp and 410 lb.-ft. of torque to the rear wheels through an eight-speed automatic transmission there is a six-speed manual gearbox available ($1,000). At 1,917 kg, the Challenger R/T is not quite as fast in a straight line, nor is it as sharp through a corner as the Mustang GT or Camaro 1SS, but the handling is forgiving and the grip levels are high.The upside is the highway ride is more comfortable. The Performance Handling group is worth the coin the $1,795 brings performance-oriented 245/45ZR20 tires, Brembo brakes and a performance steering setup.The Challenger R/T has a base price of $39,740 and a cost of $106.82 for each horsepower. It runs to 100 km/h in 5.4 seconds; does the 80-to-120 passing move in 3.5 seconds; and has a quarter-mile time of 13.5 seconds. The posted average fuel economy is 13.1 L/100 km.Sadly, the Challenger Scat Pack 392 (pictured) sits $1,445 over the $50,000 cap. However, with a $106.07 cost for each of its 485 hp, a 4.4-second run to 100 km/h, a 2.6-second 80-to-120-km/h passing time and a 12.6-second quarter-mile, it is money very well invested!2020 Kia Stinger GT AWD$123.27 per horsepowerWhen the Kia Stinger GT arrived, it raised more than a few eyebrows. With its stylish Euro-inspired five-door design, the GT added a much-needed halo car to a brand made famous by its economy rides. The GTs drive
Origin: These are the five highest-horsepower sports cars under $50,000
Under
5 Electric Vehicles for under $45K
Clockwise from top left: Chevrolet Bolt, Nissan Leaf, Hyundai Kona and Kia Niro.Handouts Its only been the last couple of years that putting together a list of five electric vehicles for under $45,000 was possible, and given the coming wave of new, affordable EVs on the horizon, a top-10 list will be do-able in the next two years or so.For now though, these five zero emission vehicles will have to do. But it should be noted that that price threshold of $45k is far from arbitrary, as that figure is the ceiling of a base priced model to qualify for a federal government rebate of $5,000 (and no, its not a coincidence the base prices of these five EVs are mere dollars, or in the case of the Tesla and Hyundai one loonie, below that threshold). B.C. and Quebec residents can further whittle down the MSRP with provincial incentives of $3,000 and $8,000 respectively. The Doug Ford government in July of last year canceled Ontarios EV rebate program.So, in no specific order, five EVs that the average family can afford.Tesla Model 3By far the best-selling EV in Canada so far in 2019 by June some 7,585 had been delivered to Canadians, compared to the second place Nissan Leaf (1,476) the Model 3 is a formidable contender and worthy of its top-selling crown. With a full-charge range between 350 and 500 kilometres (depending on the battery pack), over-the-air software upgrades and Teslas distinctive, yet spartan, exterior and interior design language, the technically advanced Model 3 exemplifies many of the best attributes of an electric vehicle. Then theres Teslas Supercharger network, which enables fast charging from coast-to-coast to the tune of up to 290 km of range is just 15 minutes. Using a Tesla 48A home wall connector charger, an hours charge provides about 70 kilometres of range. One caveat surrounding the Model 3, in fact regarding all Tesla models, is an increasing number of owner complaints about service. Specifically, how long somewhat routine repairs are taking and also the wait time for certain parts. To be sure these are, given the surge in Model 3 sales, growing pains as the company deals with a much larger footprint in Canadaparticularly in Vancouver, Toronto and Montreal. Base price (Standard Range): $44,999Nissan Leaf PlusNissan was at the forefront of the EV passenger vehicle revolution with the debut of the Leaf nearly 10 years ago, and in 2018 released the all-new, second-generation model, featuring new styling inside and out and a 40 kWh lithium-ion battery. For the model year 2019 Nissan upped the ante with the Plus model, its 62 kWh battery pack increasing the regular Leafs range by 50 per cent for an NRCan full-charge range of up to 363 kilometres. The Plus also has a more powerful motor (160 kW compared to 110 kW) that produces 45 per cent more power (214 horsepower) and a very respectable 250 lbs.-ft of torque. The second-gen Leaf benefits greatly from Nissans decade-long experience in the EV space, with advanced systems like the semi-autonomous ProPilot assist feature and the ePedal function that enables one-pedal driving perfectly suited for daily commutes in high-traffic urban centres. In terms of charging options, the Plus model offers the standard Level 1 and Level 2 ports, and adds a high output charge port (up to 100 kW) that provides an 80 per cent charge in just 45 minutes. And for those cold Canadian winters, heated seats, steering wheel and side mirrors come standard. Base Price (S Plus): $44,898Chevrolet BoltGM brought the Bolt to Canada in 2016 and set the new high-bar for range in an affordable EV with a full-charge range of 383 kilometres and a distinctively fun-to-drive personality. For 2020 theyve upped that very good range by some 10 per cent (417 km) without increasing the size or weight of the 66 kWh battery pack. That is thanks to a tweaked battery chemistry, but it does add 30 minutes to a full-charge session on a 240V system (10 hours) but improves on the DC Fast Charge time (160 km in 30 minutes). Apart from that range increase, the only real changes to the new Bolt are a textured front grille and bumper, and two new exterior colours (Cayenne Orange and Oasis Blue). One of the helpful features for Bolt owners is free access to the myChevrolet App2, with an Energy Assist function that allows you to view and search for charging stations, plan a trip with multiple waypoints and/or charging stops and receive alerts if the set route becomes invalid. A new feature of the app projects that Energy Assist screen to the Bolts infotainment system using Apple CarPlay or Android Auto. Base price: $44,998Kia NiroThe new-for-2019 Niro combines an all-electric powertrain with the popular crossover body style. Based on the gas-powered CUV of the same name, the front-wheel drive Niro EV features a liquid-cooled 64 kWh lithium-ion polymer battery with a full-charge range of 385 kilometres. Power output is 201 hp and 291 lbs.-ft of torque, and the standard DC Fast Charge
Origin: 5 Electric Vehicles for under $45K
Under the skin: Why you can always count on ABS
ABS is one of those exquisite inventions that automates cadence braking, a technique previously reserved for skilled humans, and makes the result available to everybody. Short for Antiblockiersystem, the initialism also conveniently stands for the English translation, anti-lock braking system. Introduced by Mercedes and Bosch in 1978, it’s now a standard fitment on every car. ABS not only saves lives but also, in less serious situations, a lot of tears, fights, gnashing of teeth, ‘if only’ soul-searching and money. Cadence braking is a technique used to generate the maximum possible braking force available from a tyre contact patch on a slippery surface in a given time and distance. Just as important, it allows you to maintain steering control at the same time. When a wheel is locked up on a wet road, for instance, the contact patch is generating less grip than the instant before it locked. Worse still, locked front wheels cannot steer a car. On a dead-flat skidpan, a car with all four wheels locked will drift along on the same trajectory, even if the driver twirls the steering wheel from lock to lock. To cadence brake properly (only in a car with no ABS), the driver stamps as hard and fast on the brake pedal as possible, cleanly releasing it completely each time to make sure the wheels rotate for a split second before being locked again. This does two things. It takes the contact patches to the point of maximum grip (just before the wheel locks) as frequently as possible. The effect is to provide the maximum amount of braking effort over the distance travelled. Second, each time the wheels rotate briefly, the tyre will roll in the direction it’s pointing, steering the car. ABS does a similar thing, better, and in the case of the latest Bosch ninth-generation system, 40 times a second. An ABS system consists of a unit containing electrically operated hydraulic plunger valves, an accumulator (a reservoir to store hydraulic fluid under pressure) and a pump. When the ignition is switched on, the pump pressurises the reservoir and, at the instant a wheel is going to lock, the valve controlling that brake will partially open to block further pressure to that brake, regardless of how hard the driver is pressing the pedal. If the wheel continues to lock, the plunger of the valve moves further, bleeding fluid into the accumulator. Once the lock-up has been prevented, pressure stored in the accumulator is used to reinstate pressure at the brake caliper and the process starts again and for as often as necessary. What the driver feels and hears is a high-speed juddering vibration from the brake pedal and clicking noise that feels weird, but it’s essential to keep braking as hard as possible. ABS is a wondrous technology, not just because it’s complex, but because it’s robust enough to be trusted, always. Its ability to control individual wheel braking has also enabled other major safety systems such as DSC/ESP and brake-based lane-keeping systems. Putting drivers straight Lane-keeping support, as opposed to ‘assist’, actively steers the car firmly but gently back into lane. Cameras detect the lane marking and, on cars with electric steering, the system can take partial control of it to steer. Alternatively, Bosch ABS 9 allows brakes to be gently applied on one side to steer the car in that
Origin: Under the skin: Why you can always count on ABS
Under the skin: Why modern cars need 48V electrical systems
It may not sound like it, but it’s probably one of the smartest innovations aimed at making cars more sustainable that has emerged in the past few years: 48V technology. It’s relatively cheap and fits into existing vehicle architectures but it’s only just coming of age. As well as providing a hybrid drive, it can handle loads of tasks that need doing around the car but previously used energy created by burning fuel. While 48 might look like a figure plucked out of the air after a brainstorming session in the bar, there are good reasons for it. The first is that it’s classified as low voltage and safe. Anything above 60V in a car is deemed a high-voltage system – and a high-voltage system is a lot more expensive than a low-voltage one. The safety systems, power controllers and heavy cabling involved in a high-voltage system all contribute to the high price, whether it’s 65V or 800V. Power (watts) derives from the voltage and the current (amperage). Increase either and the wattage goes up. But increasing amperage requires the use of larger, heavier, more expensive cables to reduce electrical resistance, whereas using a higher voltage and lower current doesn’t. A 48V battery is small and relatively inexpensive and installation is straightforward because a 48V electrical architecture sits alongside the car’s original 12V system. The use of 48V architectures is on the rise because the electrical consumption of cars has gone up due to more complex infotainment, connectivity and navigation systems and the dozens of driver assistance systems emerging. Cameras, radar, sensors and controllers plus the electronic systems to go with them all need more power than a 12V system can deliver. A 48V set-up also allows jobs normally done by the engine – such as powering electric water pumps, air conditioning compressors, oil pumps and heating – to be offloaded to electrical power, saving fuel. Automatic gearboxes can function when engines are shut down thanks to electric oil pumps; stop/start becomes smoother and can kick in before the car comes to a halt saving more fuel; and electric boosters in diesels reduce turbo lag. Obviously, there are limitations. Until now, the assumed maximum power of a low-voltage hybrid (or EV) motor/generator has been around 12kW (16bhp). That low, 12kW power figure has limited mild hybrids to boosting power and recovering energy, rather than providing an electric-only mode like a (high-power) full hybrid. Now, though, it looks as though that limit has been busted. Component supplier Continental AG recently announced a new 48V mild-hybrid drivetrain producing 30kW (40bhp). The improvement has been achieved by increasing the efficiency of the power control system and new design of high-efficiency, water-cooled motor/generator. The increase in power means it’s possible to drive short distances in electric-only mode like a full hybrid and makes the prospect of powering small city cars and scooters using 48V systems even more realistic. It’s the A8’s ticket to ride It may be at odds with the low-cost benefit of 48V systems but the new Audi A8 has a predictive active suspension system driven by the new electrical set-up. The system can alter the ride height by up to 85mm in 0.5sec, reacts by monitoring the road surface ahead with a front-facing camera, reduces body roll by 40% and consumes an average of 10-200W, peaking at 6kW if there’s a sharp suspension
Origin: Under the skin: Why modern cars need 48V electrical systems
Under the skin: the evolution of the automatic gearbox
Since the millennium and rapidly developing emissions legislation, automatic transmission technology has moved on at a pace. To perform economically, engines need to run in the most efficient part of their operating cycle, the ‘sweet spot’, as often as possible. To do that, they need a transmission with enough gear ratios. Autos increased from three to four gears in the 1980s and from four to five in the 1990s, but to make the jump to six took some figuring out due to the extra space needed. Epicyclic (aka planetary) gearsets are the building blocks of traditional automatic gearboxes and consist of a sun gear surrounded by three or more planet gears inside a ring gear. German transmission manufacturer ZF was one of those which succeeded in making a huge leap in automatic gearbox design in 2002 by incorporating the compact Lepelletier gearset concept with its planetary gearsets. This made it possible to fit more gear ratios into the same, or smaller space. The new gearbox was the ZF 6HP, which (no surprise) replaced the 5HP and first appeared in the fourth-generation BMW 7 Series. It moved the game on a long way, with torque-converter lock-up to prevent ‘slip’ in the fluid coupling, not just in top gear but also on all forward speeds. It could disconnect the engine from the torque converter to save fuel, too, and had a new ‘ASIS’ adaptive shift strategy. It contained only 470 components instead of the 5HP’s 660, was shorter (thanks to new compact gearsets), weighed 13% less, accelerated faster and used 7% less fuel. It also had an integrated brain called a mechatronic module, marking the departure from the engine and gearbox working independently to the new philosophy of ‘integrated powertrain’, where the engine and gearbox talk to one another. Now, the two could work together to achieve the best fuel efficiency and emissions. The 6HP later gave way to the 8HP, adding two more ratios and further refinements to make it even more efficient. Another major step, also from ZF, was the introduction of the 9HP in 2013. Designed for transverse engines, the 9HP was quite different from other automatic gearboxes. It supported stop/start systems, which others hadn’t, used a new design of internal ‘dog engagement’ clutches rather than conventional clutch packs to save space, featured nested gearsets that also helped to make it shorter and, as a consequence, was also lighter than its predecessors. The shift response was claimed to be “below the threshold of perception,” the torque converter locked up at lower speeds, it had ‘curve mode’ to stop it shifting in corners and other features making it better to drive and as efficient as possible. Some of the latest transmissions have off-the-shelf functions to work with hybrid drivetrains, such as integrated electric pumps to generate the hydraulic pressure needed to keep them working even when the engine has been shut down. Torque-converter-based automatics continue to evolve with new refinements and features and today they play almost as big a part in achieving fuel economy as the engine. Hybrid ability included In the latest hybrid automatic transmissions, electric motors do the job of a fluid-based torque converter and provide the basis for a bolt-on hybrid solution for car makers. This neat, eight-speed ZF transmission can produce up to 160bhp and has the power electronics to control it built into the casing for the first
Origin: Under the skin: the evolution of the automatic gearbox
Under the skin: How torque converters improve refinement
A fair number of different automated transmissions have been tried over the years but the most successful and enduring has to be the torque-converter-based epicyclic gearbox. New kids on the block like DCT (dual-clutch transmission) and even grown-up variants of CVT (continuously variable transmission) have threatened to knock the world’s favourite auto from its pedestal, but none has succeeded yet. That said, the classic automatic transmissions didn’t earn the moniker ‘slush ’boxes’ for nothing. The name derives from the ‘slushy’ response of early transmissions, which got people from A to B but were hardly rewarding to drive. Torque converters are fluid couplings that connect the engine to the transmission instead of a clutch. They look like large metal doughnuts but internally contain three main components plus automatic transmission fluid. The engine side is the impeller and on the transmission side is the turbine. Both contain blades and look similar to those you see in a jet engine when you’re climbing the steps to an aircraft. The impeller flings the transmission fluid outwards through centrifugal force as engine revs build and into the turbine, which is forced to rotate, driving the transmission. The fluid is forced back to the centre of the impeller in a continuous cycle. This isn’t the whole story, though, and there’s a third component that turns what would be an inefficient fluid coupling into the more effective torque converter. It’s called a stator (because it stays still) and sits between the impeller and turbine. The stator deflects the fluid on its return trip to the impeller slowing it down and, in doing so, multiplies the torque between the engine and transmission. So far so good: when the car accelerates from rest, the torque converter delivers that satisfying slingshot feeling when you put your foot down. Once at cruising speed, though, the turbine (transmission side) can never quite keep up with the speed of the impeller (engine side), increasing fuel consumption and emissions. Once those things started to matter more, transmission designers added a lockup clutch to the torque converter to mechanically lock the two halves together at cruising speed. Whereas the arrangement of the gears in a DCT gearbox resembles that of a manual, the inside of a traditional automatic transmission is quite different. Instead of gears arranged one above the other on shafts, autos traditionally use epicyclic (sun and planet) gearsets arranged one after the other in a line. Using clutches to control which way the torque is routed through each gearset creates different gear ratios. Adding more gearsets creates even more gear ratios, so three gearsets could deliver six forward speeds. Torque-converter gearboxes are clever and maybe a little fiendish, but although drivability has improved a lot over the years and they’ve always been refined, they need to become more efficient. More on how transmissions boffins achieve that next week. Why they’re so amazing Torque converters may not look much but they are one of the most amazing devices ever to grace a driveline. They take the place of a clutch, they multiply torque between the engine and the gears and they are still the choice when refinement matters
Origin: Under the skin: How torque converters improve refinement
Under the skin: How Tesla is making cars think like humans
Never mind when, can self-driving cars ever even work at all? That’s probably the question in the minds of most people. But to work, fully autonomous cars will require the invention of a machine that has the cognitive abilities of a human. The building block of a human nervous system is a neuron and millions of them form a neural network in the body’s central nervous system. To make autonomous cars a reality, computer scientists need to create artificial neural networks (ANNs) that can do the same job as a human’s biological neural network. So assuming that really is achievable, the other thing an autonomous car needs is the ability to see, and this is where opinions in the industry are split. Until recently, conventional wisdom had it that as well as the cameras, radars and ultrasonic sensors cars already have for cruise control and advanced driver assistance systems, lidar (light detection and ranging) is essential. Lidar is like high-definition radar, using laser light instead of radio waves to scan a scene and create an accurate HD image of it. One stumbling block has been the high cost of lidar sensors, which only two years ago cost more than £60,000. Lower-cost versions on the way should bring the price down to around £4000 but that’s still a lot for a single component. Not everyone believes lidar is even necessary or desirable, though, and both Tesla and research scientists at Cornell University have independently arrived at that conclusion. Cornell found that processing by artificially intelligent (AI) computers can distort camera images viewed from the front. But by changing the perspective in the software to more of a bird’s-eye view, scientists were able to achieve a similar positioning accuracy to lidar using stereo cameras costing a few pounds, placed either side of the windscreen. Tesla reasons that no human is equipped with laser projectors for eyes and that the secret lies in better understanding the way neural networks identify objects and how to teach them. Whereas a human can identify an object from a single image at a glance, what the computer sees is a matrix of numbers identifying the location and brightness of each pixel in an image. Because of that, the neural network needs thousands of images to learn the identity of an object, each one labelled to identify it in any situation. Tesla says no chip has yet been produced specifically with neural networking and autonomous driving in mind, so it has spent the past three years designing one. The new computer can be retro-fitted and has been incorporated in new Teslas since March 2019. The Tesla fleet is already gathering the hundreds of thousands of images needed to train the neural network ‘brains’ in ‘shadow mode’ but without autonomous functions being turned on at this stage. Tesla boss Elon Musk expects to have a complete suite of self-driving software features installed in its cars this year and working robotaxis under test in 2020. 50 trillion operations per second Tesla boffins say a self-driving car needs a neural networking computer capable of performing a minimum of 50 trillion operations per second (50 TOPS). By comparison, a human brain can manage about 10 TOPS. The new Tesla computer consumes no more than 100W of power so it could be retrofitted. Bosch and NVIDIA are developing a similar ‘brain’ for autonomous cars ready for 2020. It’s called the Bosch AI self-driving
Origin: Under the skin: How Tesla is making cars think like humans
Under the skin: The difference between regular and super unleaded fuel
When you pull into your local filling station, chances are there will be two types of petrol on offer: the cheaper premium grade and pricier super unleaded. So what’s your poison? Go for the super just because it sounds like a good idea, or be thrifty and stick with the premium? The most significant difference between the two is the research octane rating (RON) of the petrol. The octane rating tells you how resistant the fuel is to detonation, known as knocking or pinking. In a petrol engine, petrol is mixed with air, then it’s compressed and ignited by a spark. When that happens, the mixture burns outwards from the point of ignition like a grassland fire (but faster). The burn should be smooth and controlled, but if the mixture is compressed too much, random pockets of the mixture spontaneously detonate too early. It’s audible and can make a sound like dried lentils being poured into a tin can, or a diesel-like knocking noise. A key way of increasing a petrol engine’s performance is by raising the compression ratio, or in a turbocharged engine increasing the boost – or both. Either one increases pressure inside the combustion chamber when the fuel ignites. In older engines, the threshold at which detonation became a threat had to be carefully managed by engine designers and tuners, especially when turbos came along. Then back in 1982, Saab’s engine genius, Per Gillibrand (known as ‘Mr Turbo’), dreamed up Automatic Performance Control. APC listened for the onset of knock by using a microphone attached to the cylinder block – a knock sensor – and monitoring boost pressure and engine revs. Today petrol engines use similar anti-knock systems, but thanks to much faster processors in engine computers they can also use algorithms to predict when knock will occur. Naturally aspirated engines delay the point at which combustion is triggered (retarding the ignition) if knock threatens, all of which brings us back to the question of whether you need to fork out the extra dosh for super unleaded. The answer is, there’s only one real reason to and that is because your car has a high-performance engine or the handbook explicitly says you should use it. Using fuel of a higher octane than your engine needs or can benefit from won’t hurt it, only your wallet. The difference between premium and super unleaded these days is a maximum of two points (97 octane versus 99) and the chance of a modern engine being damaged by the lower of the two is nil. However, the engineers calibrating higher-performance engines and chasing the best performance numbers are likely to have done so using the highest-octane pump fuel available. The higher octane allows the engine to use a higher boost pressure and more aggressive settings to pump out a little more power. With the lower octane, it may back off those settings a tad to stay below the knock threshold. Whether you can notice the difference subjectively, though, is down to how attuned you are to your car. Worst case scenario Extreme cases of detonation can badly damage an engine. This cylinder head from a very highly tuned competition engine looks like it has been nibbled by rats. Rest easy, though, because there’s no chance of anything like this happening to a production car by choosing premium petrol over super unleaded at your local
Origin: Under the skin: The difference between regular and super unleaded fuel
Under the skin: How manufacturers are preserving pistons
“Reports of my death are greatly exaggerated,” said Mark Twain after an erroneously posted obituary. It’s pretty much what every internal combustion engine would say, too, if they could speak. While hysteria over the car’s contribution to emissions reaches epic proportions, engineers everywhere are working hard to improve internal combustion engines (ICEs) to drive toxic and CO2 emissions down. The Hyundai Motor Group’s new CVVD (continuously variable valve duration) technology is the latest ICE development to break cover. It’s another example of how new engineering techniques are enabling engineers to revisit the engine fundamentals to leap technical barriers that were once insurmountable. CVVD on the new Smartstream G1.6 T-GDi engine, to be fitted to both Hyundai and Kia cars, improves performance by 4%, fuel efficiency by 5% and emissions by 12%. Inlet and exhaust valves in the cylinder head of an engine let fuel and air in and exhaust out. When they open and close and by how much depends on what an engine is designed to do. Valves are opened by cams, offset lobes positioned along a camshaft, one for each valve. So a four-cylinder four-valves-per-cylinder twin-cam engine would have an exhaust cam and an inlet cam, each with eight cam lobes, one for each valve. The shape of the cams is designed to control the lift and the duration (length of time they stay open). How progressively they open and close and at what speed is down to the shape of the cam. In engine tuning, there are lots of different camshafts to choose from to give the characteristics the engine builder wants. The design for a normal, tractable family car engine at one end of the scale will be totally different from the ‘hot cam’ of a race engine at the other. Clever tech such as BMW’s Vanos varies the valve timing (when the valves begin to open and in relation to the position of the piston and moment of combustion). A second system, Valvetronic, can alter valve lift. Used together, both timing and lift are variable. The ingenious Multiair system, developed by Fiat Powertrain Technologies with the Schaeffler Group, can vary both timing and lift with some cunning electro-hydraulics. Jaguar Land Rover also uses a version of the Schaeffler tech on its Ingenium petrol engine. Honda’s famous VTEC cam-switching system is devilishly clever but simple by comparison. It has two cam lobes per valve arranged in pairs on the camshaft. The engine can select a softer, more tractable profile at lower engine speeds and switches to the hotter profile to get more gas in and out at higher revs for maximum power. CVVD works on the inlet valves (but can be applied to the exhaust valves, too) by moving the centre line of the camshaft slightly from side to side, altering the position of cam lobes on the valves. CVVD is yet another step forward in the history of the ICE, and although most bases in terms of engine breathing have probably been covered now, don’t be surprised if engineers find some more tweaks to improve efficiency still further over the next few years. Pump it up Fiat’s Multiair system can control lift and, to a lesser extent, timing but not duration. Instead of acting directly on the top of the valves, the cams operate tiny oil pumps in the cylinder head, generating hydraulic pressure to open the valves. Electronically controlled bleed valves can release pressure to alter how much the valves open and make them open later or close
Origin: Under the skin: How manufacturers are preserving pistons
Under the skin: Why hydrogen could be an easy cell
Twenty years ago, DaimlerChrysler, as the two merged companies were called then, launched the A-Class-based Necar 4, the first production-ready fuel cell vehicle capable of being driven on public roads. The plan was for the first commercial version, dubbed, ‘Necar X’ to be launched on public sale in 2004. By that time, DaimlerChrysler said it would have spent over £1.1 billion on fuel cell vehicle development: it was that big and looked that certain. The board member responsible for RD, Klaus-Dieter Vöhringer, said back then: “From 2004 to 2010, the population of fuel cell vehicles has to increase very fast otherwise the (refuelling) infrastructure will not grow.” He was dead right in one sense: it didn’t grow and fuel cell cars haven’t taken to the roads in large numbers. Yet. Some would say hydrogen fuel cells are the holy grail of sustainable propulsion because they emit nothing except water and heat from the tailpipe. So long as the hydrogen fuel they consume is produced sustainably, it’s an environmental free lunch with refuelling pretty much as easy and fast as it is with petrol or diesel. In common with a battery, a fuel cell ‘stack’ consists of hundreds of individual cells producing a little over one volt each. The favoured technology for cars and transport is the polymer exchange membrane (PEM) fuel cell. A fine polymer membrane sandwiched between a platinum cathode and anode and two flow plates in a kind of double-decker sandwich make up each cell. Hydrogen travels through the flow plates on the anode side while air is pumped through the cathode side as a source of oxygen. Hydrogen protons are attracted through the membrane to the oxygen, making water, leaving the hydrogen electrons behind, forming a current in an external circuit. There have been lots of technical hurdles to overcome – including scavenging residual water from inside the cells, which would freeze at low temperatures, starting the stack in sub-zero temperatures, economic manufacture and robustness – but today fuel cell systems are advanced, if still pricey. An entire fuel cell system consists of a stack, a carbonfibre tank capable of storing hydrogen at 750 bar and a small lithium ion battery to deliver both the fast surge of power needed for acceleration and to store energy from regenerative braking. Tough hydrogen tanks split and release hydrogen rather than exploding if damaged and, in that sense, the world’s most plentiful element is safer than petrol. The rest of the powertrain is like that of any other electric car, with an electric motor and power control module to manage it all. It’s also 20 years since the formation of the California Fuel Cell Partnership, one of the world’s largest institutions pushing the development of fuel cell technology. With its 2030 Vision programme, it aims to get 1,000,000 fuel cell vehicles on California roads along with 1000 hydrogen filling stations by 2030. Maybe then, the fuel cell ball will really start rolling. New train of thought Hydrogen fuel cells are ideal for large vehicles as well as cars. Two Coradia iLint fuel cell trains from French firm Alstom have been running in Germany since 2018 and 27 more have been ordered by a transport authority. A Hydroflex train masterminded by the University of Birmingham and train maker Porterbrook began UK trials in
Origin: Under the skin: Why hydrogen could be an easy cell
All about car 