Toyota introduced a pair of brand-new engines in Japan today, that it says will eventually spawn 14 different variants by 2015. Where these two engines stand out in today's world, is that neither mill boasts direct injection, and both are naturally aspirated.

The larger of the two is a 1.3-liter, while the smaller engine, a 1.0-liter, was developed in collaboration with Daihatsu. What makes these two unique is that they both use the Atkinson cycle. Now, we aren't going to bore you by explaining just what this is - there's Google for that. Suffice it to say, Atkinson engines are highly efficient, but that efficiency comes by sacrificing power. That's why they're so popular in hybrids, which can offset the power losses.

This focus on fuel efficiency extends throughout the new engines, which also benefit from tweaks like a cooled exhaust gas recirculation system and a trick intake port, while the 1.3 employs Toyota's iE variant of variable valve timing. Both engines can be fitted with stop-start tech. According to Toyota, when fitted with stop-start the 1.3 should provide around a 15-percent bump while the 1.0-liter will increase economy around 30 percent, when they arrive on the road.

We're not going to lie, the non-hybrid Atkinson system is a question mark. But according to General Manager of Powertrain Planning Shouji Adachi, it shouldn't be an issue.

"There is always the challenge of lower performance in torque," Adachi-san told Automotive News. "For the new engines, we were able to resolve these issues."

We're presuming that what Adachi is referring to is Toyota's use of high compression ratios on both engines - 13.5 in the case of the 1.3L and 11.5 in the 1.0L. Using a higher compression ratio allows the engine to develop more power thanks to increased thermal efficiency. In the case of the 1.3L, max thermal efficiency is at 38 percent, which Toyota says is quite good. The 1.0L is just a smidge behind, at 37 percent.

So, power concerns momentarily swept aside, where to do we think these engines will end up? According to AN, non-hybrid, JDM compacts will be the first to use the new engines. From there, though, it's really anyone's guess where these engines and their variants will end up. Scroll on down for the short press release on the two engines, from Toyota.
Show full PR text
Toyota Develops Engines with Improved Thermal, Fuel Efficiency

Toyota City, Japan, April 10, 2014―Toyota Motor Corporation aims to further increase the environmental performance of its vehicles with a series of newly-developed, highly fuel-efficient engines that achieve outstanding thermal efficiency1. The new engines leverage combustion and loss-reduction technologies Toyota has refined in its dedicated hybrid engines, and will achieve fuel efficiency improvements of at least 10 percent2 over current vehicles. The engines will be used in models scheduled for partial redesign in the near future, and a total of 14 new engine variations will be introduced globally by 2015.

One of the engines is a 1.3-liter gasoline engine in which Toyota is employing the Atkinson cycle3―normally used in dedicated hybrid engines. Use of the Atkinson cycle provides an increased expansion ratio and reduces waste heat through a high compression ratio (13.5), resulting in superior thermal efficiency. Toyota aims to further improve the fuel efficiency of the engine by utilizing other innovations including an intake port with a new shape that generates a strong tumble flow (whereby the air-fuel mixture flows in a vertical swirl) inside the cylinder, and a cooled exhaust gas recirculation (EGR) system paired with Variable Valve Timing-intelligent Electric (VVT-iE) technology to improve combustion and reduce loss. As a result, the new engine will have a maximum thermal efficiency of 38 percent4―top-level among mass-produced engines. The new features, combined with idling stop and other functions, will lead to fuel efficiency gains of approximately 15 percent2 by comparison with current vehicles.

Meanwhile, a 1.0-liter engine jointly developed with Daihatsu Motor Co., Ltd. has achieved maximum thermal efficiency of 37 percent4 due to a similar tumble flow-generating intake port, a cooled EGR system, and a high compression ratio. Combination with the idling-stop function and various other fuel consumption reduction technologies allows vehicles to achieve a maximum fuel efficiency improvement of approximately 30 percent2 over current vehicles.


I'm reporting this comment as:

Reported comments and users are reviewed by Autoblog staff 24 hours a day, seven days a week to determine whether they violate Community Guideline. Accounts are penalized for Community Guidelines violations and serious or repeated violations can lead to account termination.


    • 1 Second Ago
  • 22 Comments
      bullitt2605
      • 8 Months Ago
      They will probably still connect them to a 4 speed tranny.
      Spec
      • 8 Months Ago
      Put it in a plug-in hybrid, Toyota.
      Finklestein
      • 8 Months Ago
      This is what happens when you use appliances as templates for car design
      normc32
      • 8 Months Ago
      Turbo, DI, turbo, DI...poop!
      carguy1701
      • 8 Months Ago
      Itty bitty engines!
      Master Austin
      • 8 Months Ago
      Thats one thing toyota hasn't invested much on is powertrain. Like Corolla with the 28 year old transmission. And the V6 that is hitting 20 years with minimal changes. So this is welcomed.
        carguy1701
        • 8 Months Ago
        @Master Austin
        "And the V6 that is hitting 20 years with minimal changes." What the **** are you talking about? Toyota has changed V6 families TWICE in the last 20 years. The VZ engines gave way to the MZ engines, and those engines were themselves replaced by the GR engines!
      jebibudala
      • 8 Months Ago
      3 bangers sound awesome. Just listen to this beast! http://www.youtube.com/watch?v=wW8kK6f7v1c
      bonehead
      • 8 Months Ago
      Can someone make me an S2000 or MR2 replacement with a 2.0L turbo V6 and 10000 rpm redline. KTHXBYE
      ScottM
      • 8 Months Ago
      So basically Toyota 'liberally borrowed' the Skyactive Tech. I guess we know now why Mazda is going to be able to use their hybrid technology now....
        chanonissan
        • 8 Months Ago
        @ScottM
        forget to add the production nissan HR12DDR uses a compression of 13:1 for a small engine. http://en.wikipedia.org/wiki/Nissan_HR_engine
      Mbukukanyau
      • 8 Months Ago
      hope they come with emergency shut off and a recall address
      Michael
      • 8 Months Ago
      Atkinson+cycle&safe=off? I'm assuming this article was posted from a home computer...
      Basil Exposition
      • 8 Months Ago
      With stuff like this I can't imagine why Toyota is outsourcing small engines from Mazda. http://www.autoblog.com/2014/03/08/toyota-will-use-mazda-skyactiv-engines/
        finzenchrome
        • 8 Months Ago
        @Basil Exposition
        Actually I think these new engines are the Toyota-branded versions of Mazda's Skyactiv-G.
    • Load More Comments