Mazda is looking to return to its roots when the next generation MX-5 Miata debuts. According to a report by InsideLine, the car will take inspiration from the MX-5 Superlight Concept and weigh just 2,200 lbs. Mazda has already announced that starting in 2011 it aims to cut the curb weight on all of its new models by at least 220 lbs.

Even more impressive is that it is expected to use the company’s new SKY-G engine, which Mazda debuted recently at the Tokyo Auto Show. Displacing just 1.3-liters, this 4-cylinder isn’t a hybrid or a diesel, but reportedly makes as much as 150-hp and can get anywhere from 50-mpg to 70-mpg!

Mazda has yet to reveal how it managed to get such a high fuel economy number out of this setup, but InsideLine is reporting that industry juggernaut Toyota is impressed and interested in the technology.

Recently Mazda did show a hybrid version of the SKY-G engine in its Kiyora Concept which debuted at the Tokyo Auto Show. Powered by the same 1.3-liter version of Mazda’s new SKY-G engine combined with a six-speed Sky-Drive automatic transmission, Mazda’s i-stop start/stop system and regenerative braking, Mazda says it can achieve 75 mpg.

[Source: InsideLine]

Just after publishing an article on Mazda’s new SKY engines, which are set to debut at the Tokyo Auto Show in October, Mazda sent us a press release on the Kiyora Concept car.

This new vehicle, which is set to debut at the Tokyo Auto Show, is powered by a 1.3-liter version of Mazda’s new SKY-G engine combined with a six-speed Sky-Drive automatic transmission. With a light-weight body as well as Mazda’s i-stop start/stop system, regenerative braking and an aerodynamic body that is 220 lbs lighter than any body in the compact car segment, the Kiyora Concept gets an incredible 75 mpg.

The Kiyora Concept and the SKY engines and transmissions embody Mazda’s environmentally responsible commitment to ensure an “everlasting blue sky,” while keeping with the company’s focus on driving enjoyment and the “sky’s the limit” philosophy of the company’s engineering department.

For more on Mazda’s new, fuel-efficient and more powerful engines and transmissions, which will debut at the Tokyo Auto Show, see our article here:

Report: Mazda Previews New, More Powerful and Fuel Efficient Sky Engines

GALLERY: Mazda Kiyora Concept

Official release after the jump:

Ahead of their official debut at the Tokyo Auto Show, Mazda has decided to give us just a small preview of what the company’s vehicles could be powered by in the near future. Both a new gasoline and diesel engine have been announced, as well as a new transmission, all under the catchy SKY brand.

First up is a new SKY-G 2.0-liter motor, that uses direct injection to improve both torque and fuel-economy by roughly 15 percent. Mazda hasn’t officially said anything about producing the motor or what car it will find its way in to, but we’d expect to find it in the Mazda3, replacing the top-level 2.5-liter four-cylinder, making roughly the same horsepower (around 170), while getting fuel-economy closer to the base 2.0-liter’s 24/33 mpg rating.

A new SKY-DRIVE transmission will also be available, which Mazda says will help improve fuel-economy by five percent. Unfortunately, this is not a fancy dual-clutch tranny, but Mazda does say it will be faster with more engaging shifts. Still being rather secretive, Mazda has not said how many gears there will be, but we suspect the improvement in fuel economy is due to the addition of a sixth gear.

Finally, Mazda unveiled a new SKY-D diesel motor, which we can be quite certain won’t make its way to North America. It uses a two-stage turbocharger with piezo injectors and some modifications of the engine structure to deliver a 20 percent improvement in fuel economy over the current 2.2-liter diesel.

We’ll be sure to bring you updates on all of these new drivetrain options when Mazda officially unveils them at the Tokyo Auto Show on October 21st.

[Source: LeftLaneNews]