The Latest News from Around the Industry
From a truck standpoint, particularly a diesel truck standpoint, the North American International Auto Show brought a mixed bag. Volkswagen and its suite of brands including Audi and even Porsche are out of the diesel business in North America, to no one’s surprise. Conversations with Asian manufacturers of some great diesel engines, for instance Honda and Hyundai, produced the same “we see no point—at this point” comments as in years past. We think competitive forces might—and it’s a 5 percent chance, at most— push Honda to bring their European diesel engine into North America solely for the well-reviewed Ridgeline pickup.
Good diesel-related news did arrive from Ford, GM and Mazda. Ford spoke about its upcoming 3.0-liter Power Stroke engine, and GM delivered a 1.6L diesel packing 137 SAE certified horsepower and 230 lb-ft of torque. (See an Inside Look into the new GM Diesel starting on page 44 for more details on this new baby diesel.—ed.) Mazda officially told us that Ultimate diesel builders guide is on a short list for first view of their Skyactiv diesel, coming “Real Soon.” So we said, “We assume a similar engine to the original Skyactiv diesel, but with SCR.” Scarcely a wink-wink, nudge-nudge, but that’s the story. We’ve included what we think that engine will be like.
FORD 3.0L DIESEL FOR F-150
In Detroit, Ford surprised every attending journalist; they didn’t show any new product during their press conference. Instead they talked about the forthcoming 2020 Bronco and Ranger in 2019, both all-new products. Then Ford semi-surprised us, announcing a 3.0-liter V6 Power Stroke diesel engine for F-150. We’re sure it will be similar to the Range Rover V6, and built by Ford at their Dagenham Engine Plant in Essex, England. Ford, though releasing zero specifics, says the engine was designed and engineered in-house with all the testing and certification done by and at Ford. We can only hope and speculate that the Bronco and Ranger will also have diesel offerings either in the new 3.0L Power Stroke or the I5 3.2L Power Stroke diesel used in the Transit van.
For an idea of what to expect, JLR’S 3.0L diesel, the Td6 turbo V6, is rated at 254 horsepower and 444 lb-ft of torque. You’ll recall Ford owned Jaguar Land Rover at one point and JLR’S engine evolves from a baseline, the Lion engine created in a partnership between Peugeot, Ford, and Rover. We think the Ford’s new motor will deliver very similar power, as there’s not much more to pull out of three liters reliably. To achieve better fuel economy than the current V6 Ecoboost engine, the new Power Stroke diesel will be equipped with a new 10-speed transmission Ford jointly developed with GM. Then to further improve fuel economy the transmission, and all F-150s using that transmission, will have integrated stop-start and an e-pump to keep the gears lubricated; that should produce seamless restarts.
That 10-speed is the first all-alloy Ford gearbox. In all, two pounds were shaved off the new, slimmer transmission. There will be a Sport mode and, for towing, an even smarter tow/haul mode. The transmission’s logic control uses “real-time-adaptive shift-scheduling algorithms that monitor more than a dozen powertrain and driver control signals,” according to Ford. That’s to put you into the right gear every time.
MAZDA 2018 SKY ACTIVE DIESEL, PURE POWER AND IMPURE SPECULATION.
Skyactiv, Mazda’s name for their latest gas and diesel powertrains, debuted in 2011. Wow! That’s six years since our expectation that the diesel would be available for 2012/2013 model CUVS. Obviously they never arrived. Despite impressive engineering prowess they could not meet their stated goal of meeting Euro6 and USA Tier2bin5 emissions standards and achieve internal Mazda Zoom-zoom, fun-to-drive guidelines without a NOX catalyst.
At the Chicago Auto Show we were told that the engine was fully capable of meeting EPA requirements, just that it wasn’t Zoom-zoom. Thus SCR and, we’re told, a downstream secondary NOX sensor suggested
by the EPA. Sources told us we should expect output of around 300 lb-ft; that’s a chunk of torque. The engine will still displace around 2.2-liters and (we think) keep Mazda’s low-low 14:1 compression ratio as they were close to their numbers without NOX traps and SCR. Lately most diesel engine manufacturers have dropped the compression ratio down from historic 22:1 or 18:1 to 16:1.
Mazda planned, at the launch event, to use injection timing to achieve cleanliness by initiating expansion, the power stroke, at different part of the combustion cycle, after Top Dead Center. The only way this is possible is with microprocessor-controlled multiple fuel injections, now common for virtually all internal combustion engines. According to Mazda, if you inject fuel at TDC the temperature and pressure are high. They say this often means there is a lack of uniformity in the fuel-air mixture. Any regional lack of oxygen in the combusting fuel-air mix creates soot or particulate matter. By lowering the compression ratio, temperatures don’t rise as quickly (as fuel is burned) and there is more time for the fuel to mix with air. This relates not only to soot formation but to nitrogen oxide formation (NOX) and an increase in fuel economy.
Mazda says another factor, expansion ratio, or the amount of work each piston does on each ignition-expansion stroke, is hugely affected by compression ratio. Mazda figured that if they lowered the compression ratio and ignited at TDC the duration of stroke that was used as the fuel burns and expands would increase. According to their numbers, their diesel generates in-cylinder pressures of 130 kg/cm2 versus typical 170 kg/cm2 or 1860 psi versus 2430 psi and the length of stroke (and time) when expansion pressure does work is greater than conventional diesel engines.
If you think about less pressure in the cylinder, you’ll come to the same conclusion Mazda engineers did: Less pressure inside each cylinder—and the whole engine—means the cylinder block can be less robust. Whoa! That leads to even more, as with less pressure every component in the engine can be subtly less robust without sacrificing durability. The 2.2-liter engine block is made of aluminum and is 25 kg lighter (55 pounds) than their current diesel. Its aluminum cylinder head has thinner walls, an integrated exhaust manifold, and saves 3 kg (6.6 pounds). Pistons are thinner and 25% lighter and the crank is 25% lighter with smaller journals (52 mm versus 60 mm).