Automotive

Toyota unveils advanced engines for 2017 and beyond

Toyota unveils advanced engine...
Mated together, the 2.5-liter engine and eight-speed transmission form a complete package for Toyota's new TNGA-based powertrain architecture
Mated together, the 2.5-liter engine and eight-speed transmission form a complete package for Toyota's new TNGA-based powertrain architecture
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This cutaway shows the hybrid drive transmission with changes made for the new-generation THS-II to be used in Toyota hybrid vehicles going forward
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This cutaway shows the hybrid drive transmission with changes made for the new-generation THS-II to be used in Toyota hybrid vehicles going forward
Toyota shows its powertrain evolution in terms of efficiency gains
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Toyota shows its powertrain evolution in terms of efficiency gains
The Toyota New Global Architecture (TNGA) 2.5-liter engine is high-compression, direct-injection, and much more efficient than outgoing engines of similar size
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The Toyota New Global Architecture (TNGA) 2.5-liter engine is high-compression, direct-injection, and much more efficient than outgoing engines of similar size
This TNGA transmission is Toyota's new eight-speed automatic for use in transverse applications (front-wheel drive)
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This TNGA transmission is Toyota's new eight-speed automatic for use in transverse applications (front-wheel drive)
This ten-speed automatic is the new transmission developed for TNGA and to be used in rear-wheel drive vehicles
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This ten-speed automatic is the new transmission developed for TNGA and to be used in rear-wheel drive vehicles
Mated together, the 2.5-liter engine and eight-speed transmission form a complete package for Toyota's new TNGA-based powertrain architecture
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Mated together, the 2.5-liter engine and eight-speed transmission form a complete package for Toyota's new TNGA-based powertrain architecture
Key to hybrid drive efficiency was the development of this new power control unit (PCU) to tie it all together
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Key to hybrid drive efficiency was the development of this new power control unit (PCU) to tie it all together
New and advanced lithium-ion batteries will give more range and capability to Toyota's upcoming plug-in hybrid vehicles
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New and advanced lithium-ion batteries will give more range and capability to Toyota's upcoming plug-in hybrid vehicles

Toyota has unveiled new engines based on its Toyota New Global Architecture (TNGA), to be used in both standard gasoline and hybrid vehicles. The company says that the recently-developed, more efficient engines will begin rolling out in 2017.

Toyota will introduce 17 versions of nine new engines and 10 versions of four transmissions from 2017 to 2021. These will be combined with new electrified components for 10 versions of six new hybrid-electric drive systems in that timeframe. With TNGA, Toyota is changing the car almost fundamentally, to aid every aspect of efficiency, it says. Ride height, hood angles, drivetrain weights, and more are all aspects of improving the efficiency of the automobile.

The modular design of the TNGA engines and transmissions allows for the mixture of versions that Toyota will be rolling out over the next few years. The company is targeting 10 percent better power performance (measured by vehicle 0-60 mph/0-92 km/h times) and 20 percent better fuel economy. The new TNGA engines are called "Dynamic Force Engines" and combine loss reduction (lower energy losses), improved fuel combustion, and improved air intake efficiency.

The first engine in this new architecture is a 2.5-liter four-cylinder that achieves 40 percent thermal efficiency as a gasoline-only engine, and 41 percent when used in a hybrid system. Toyota is showcasing this new engine as its illustration of TNGA. The current average for four-cylinder engine thermal efficiency is about 36.8 percent.

The 2.5L engine uses high-speed combustion and variable intake control to create strong air tumble and volume inside the cylinder. This spreads the fuel into the air to make for better combustion. The stroke-bore ratio of the engine is 1.2, balancing power outputs. The engine has a wider valve (41 degrees) which allows for better intake/exhaust. New valve seat materials and laser valve seat cladding mean lower friction losses as well.

The engine runs with a 13:1 compression ratio for gasoline-only and 14:1 for a hybrid system. High-energy ignition coils, multi-hold direct injectors, and cylinder bore and piston coatings complete the package. All of these combine to provide better thermal and friction efficiencies in the TNGA engine.

These efficiency gains result in better fuel economy and lower particulate emissions from the engine. On that latter point, Toyota is targeting 60 percent reductions.

To go with the new TNGA engines, Toyota has also developed new transmissions. A new eight-speed automatic and a new ten-speed automatic (8AT and 10AT) are being introduced. Improvements in gear tooth surfaces and clutch materials reduce friction throughout the transmissions. Clutch torque loss is reduced by approximately 50 percent, Toyota says, when compared to its conventional six-speed automatic.

The new transmissions are both lighter and more compact than those they will replace, offer a lower center of gravity, and feature a newly-developed high-performance torque converter. Toyota did not offer more information on this new unit except to say that it's smaller and more efficient than conventional torque converters.

Toyota also introduced its Toyota Hybrid System II (THS-II) as part of the TNGA rollout. These are loss-, size- and weight-reducing powertrains that also introduce the newest generation of the company's hybrid line. THS-II involves both a transverse and standard (rear-wheel drive) transmission fitted with electric motors. This hybrid system is a natural evolution of the current Hybrid Synergy Drive, involving one electric motor acting as a generator and another as a power unit for the drivetrain. A new, smaller, lighter power control unit (PCU) reduces electrical loss by about 10 percent and is mounted directly above the transaxle, making for space savings.

The motors are newly-developed and use magnetic steel and a rolling coil structure, which uses fewer wires. A parallel reduction gear reduces power transfer losses, and both the motors are smaller and lighter than before while offering similar or better power output when compared to those they'll replace. Toyota claims that when combined with the 2.5L Dynamic Force engine, this transaxle produces 20 percent better fuel economy and has acceleration improved by 10 percent.

Toyota shows its powertrain evolution in terms of efficiency gains
Toyota shows its powertrain evolution in terms of efficiency gains

Toyota has also enhanced the plug-in hybrid (PHV) performance through similar motor enhancements coupled with more efficient lithium-ion batteries with higher capacity, allowing for more range and higher-speed electric-only driving.

Toyota says that these improvements will begin rolling out in 2017, debuting on an as-yet-unnamed new vehicle model to be introduced soon. The new TNGA powertrain units will be featured in 60 percent of the company's lineup of vehicles by 2021. They will appear globally.

Source: Toyota

11 comments
VincentWolf
It's not electric so it's not advanced.
LanceTurner
Ho hum, even more complexity and more to go wrong, more expense when it comes time to repair it. Look at that motor/transmission system, and compare it to an electric drive, the ICE is a joke. Hell, if you took an electric drive and a ICE drive and showed them to an engineer from another planet, who had never used cars, and said "which one makes more sense", the answer, of course, would be the electric drive. The whole ICE industry is resisting the move to EVs for one reason only - the money they make from spare parts is most likely greater than what they make from initial vehicle sales, over the life of each vehicle. But, the world is transitioning to electric transport, anyone not onboard with that will go the way of the Dodo, and good riddence.
SuperFool
Things like the motor driven water pump might not be the best idea. independent parts that drive critical functions will be a problem when the cars warrantee runs out. so it's good for maybe 10 yrs then 20 things start to fail and maintenance is more trouble than buying a new one, which is the whole idea and I don't like it.
habakak
It's incredible how much more efficiency engineers wring out of the ICE and accompanied gearboxes. But it's just no competition for the simplicity and reliability of an electric motor (without a gearbox). Electric cars are still expensive, but within 3 years cost, range and charging ability won't be a problem for mainstream affordable electric cars anymore. The ICE has served us well, but it's dawn is fast approaching.
Martin Hone
A re-hash of a Toyota press release. C'mon guys, how about some explanation of the so called advances or improvements ? What does this mean ? "The stroke-bore ratio of the engine is 1.2, balancing power outputs. The engine has a wider valve (41 degrees) which allows for better intake/exhaust. New valve seat materials and laser valve seat cladding mean lower friction losses as well." How does the 1.2 ratio effect power output ? A wider valve ? You mean wider valve angle. And how does new valve seat material produce lower friction and what the hell is laser valve seat cladding ???
ljaques
I'm thrilled to see the 8-speed tranny. If this engine and tranny in hybrid mode were available for my '07 Tundra, it would have been a great combo and I would have snatched it up. Yes, with that tranny, it would have more power than I'd need for anything except towing large trailers. I wonder if they'll do a trade-in on my 4.7L V-8...
Augure
Well done Toyota...for 3 persons who'll give a shit while the rest of us is investing in electric motors.
Chishiki
The world has to work with what works now. Not what will work in the future. That is why ICE will continue to advance. Electric cars have a major cost problem. Even at 35k, that is very expensive. Then there is the fact you can't use electric in any application where weight is a serious issue. What caught my attention was this engine. They have a working engine at 40% efficiency. I calculated that off of the 186 g/kwh on diseal fuel. It can potentially get a lot more efficient. It delivers 40 hp while weighing 30 lbs. Very few moving parts. They are saying one of their engines with one type of fuel can get 2hp/lb. http://liquidpiston.com/technology/engine-benefits/ http://newatlas.com/liquidpistol-rotary/24623/ http://www.nextbigfuture.com/2016/12/darpa-funds-30-kw-x4-liquid-piston.html
Bob Smogango
Here's something to THINK about for all of the people writing nasty comments about this engine technology and only thinking all electric. First off, all electric vehicle represent and VERY, VERY small percentage of the market and other than the Tesla's, the rest of what's shipping gets horrible range. these electric manufacturers like Tesla, have to keep pace with building charging stations, otherwise, you have to wait in line at a charging station if it's near a major area since there are more electric cars and not enough charging stations. In addition, most all electric vehicles are vastly more expensive than traditional combustion and Hybrid cars. So for the time being, traditional combustion and hybrids are going to be the majority of the market and it's going to take AT LEAST 10 more years until All Electric makes a significant dent in total car sales. Electric vehicles have several major hurdles. 1. Battery cost. 2. Battery Range. 3 Charging stations
tsvieps
Our 2013 Prius Plugin has averaged 68 mpg, ignoring the 2.4 cent per mile electric fuel costs. @ $25k, we paid only a few hundred dollar premium over the standard Prius. The next Plugin will have 2x the electric range. We would achieve about 85 mpg with it, I think. Even without the Fed subsidy, it should also be available for around $25k. Once one gets to such a range for gas efficiency and considering its 700 mi range, such a car is quite a deal. I think it will be at least a decade before an all electric can compete with its practicality and economy.