Among the more than 100 automakers in the world, we got off to a late start as the 90th company to venture into the market. Yet we managed to independently develop an engine, a feat only claimed by 12countries in the world. Kia Motors R&D Center received US$57 million in royalties from Mitsubishi and Chrysler for its world-renowned Theta engine. With numerous tests simulating different situations which may arise while on the roads, we are recognized for having the world’s best safety technology for enhanced driver and passenger protection.

Power and innovation

The Powertrain R&D Center develops the heart of all motor vehicles, from compact cars to luxury sedans and commercial vehicles. The Center researches and develops engines, transmissions and eco-friendly exhaust systems. With our full line-up of proprietary technologies, we are creating industry-leading powertrains recognized the world over.

Class-best powertrains

We realized automotive independence by developing the first Korea-designed Alpha engine and transmission in 1991. In 2004, it achieved another milestone by developing Korea’s first export engine, the Theta World engine. In 2006, we developed our class-leading 3.0L V6, the S-engine, to power the Mohave. With the Tau 4.6L engine named one of Ward’s 10 Best Engines in 2008 and our R-passenger diesel engine becoming the first Korean engine to be Euro 5-compliant and Seoul metropolitan area low emission vehicle certified, Kia’s engine technology is receiving accolades at home and abroad.

Next-generation, high-performance, environmental transmission

We are harnessing our accumulated independent development ability to lead the global transmission market. Kia has focused on high-performance, environmentally friendly transmissions that reflect diverse customer needs. In 2009, we completed development of the internationally competitive, front wheel drive six-speed automatic transmission and Continuously Variable Transmission (CVT) for hybrid LPi vehicles.

Environmentally-friendly exhaust systems

In response to increasingly stringent regulations on exhaust emissions, the Powertrain Center is stepping up its efforts to develop technologies that raise fuel efficiency, lighten vehicle weight, lower friction and improve driving power. Additionally, the Center is working on development of powertrains for hybrid electric vehicle.

Downsizing: Efficiency demanded by reality

‘Achieving the output of a 3.0 engine with a 2.0 engine.’ The goal of downsizing is reducing the size and weight of powertrains while maintaining or improving performance. A large engine is powerful but has poor fuel economy, while a small engine has good fuel performance but falls behind in terms of power. To discredit this commonly-held perception, a wide range of technologies are being applied to raise engine output and fuel economy while reducing CO2 emissions.
The five key downsizing trends and technologies are as follows: turbocharger technology, direct injection technology, multi-step automatic transmission (or dual-clutch transmission), Idle Stop & Go (ISG), and technologies for going lightweight.
Turbochargers enhance the power of small engines. Decreasing engine displacement is crucial to downsizing because a 30% reduction can lead to a 15% improvement in fuel economy, while a 50% reduction raises fuel economy by 25%. Downsizing the engine reduces the engine’s power. To make up for this loss, the turbocharger uses the engine’s exhaust to power the turbine, which in turn, powers the air compressor that supplies the engine with pressurized air.
Direct injection (DI) raises fuel economy by 8-10% by supplying fuel directly into the cylinders. K7 (Cadenza) and K5 (Optima) are powered by gasoline direct injection (GDI) engines.
Receiving the most attention these days among multi-step automatic transmissions is the dual-clutch transmission (DCT). DCT boasts both the affordability of a manual transmission and the convenience of an automatic transmission. A DCT is about 12% more fuel-efficient than an automatic transmission of the same gear range. Kia Motors has developed a DCT with a gear shifting speed of 0.04 seconds, which provides enhanced fuel economy and driving performance. This upgraded DCT will be installed in Kia’s new models starting in 2011.
With Idle Stop & Go (ISG), the engine shuts down when the car comes to a stop and starts back up again when the car begins to move. Venga and cee’d, customized models for the European market, are the only two Kia cars so far to be equipped with ISG. This is because related trends have been gaining popularity in Europe and also because there are no standards in Korea against which ISG can be certified. However, we are planning to expand the application of ISG to domestic models starting with Forte Eco Plus, set to be released in 2011. The lighter the vehicle body is, the greater the fuel efficiency and performance become. Accordingly, technologies for making lighter vehicles make up an important part of the downsizing equation.

Engine downsizing

We present the latest in engine downsizing technologies using K5 (Optima) and Sportage R as examples. In a GDI engine, fuel is injected directly into the cylinders, maximizing the air supply to the engine and enhancing performance.
GDI prevents knock (pinging), thereby raising thermal efficiency by 2-3%. It also adjusts the timing of fuel injection, minimizing the emission of harmful exhaust gases that occurs when the engine is first ignited. K5, equipped with the Theta GDI engine, satisfies Korea’s 09EM regulations and the strengthened requirements to qualify as a partial zero emission vehicle (PZEV) in North America. It outperforms its competitors with 201-horsepower output and has a high fuel economy of 13.0 km/ℓ. The application of GDI engine technology will be expanded to newly-released models.
The R engine in Sportage R and Sorento R features a 1,800-bar high-pressure fuel injection system that cuts exhaust emissions while raising fuel efficiency and engine output. The R engine is a high performance, eco-friendly diesel engine for passenger cars. Sorento R, equipped with our proprietary FWD 6-speed automatic transmission along with the R engine, boasts fuel economy of 15 km/ℓ, a 38% improvement over the former Sorento (10.9 km/ℓ).

Technologies for transmission enhancement

Transmissions also play an important role in determining fuel economy. The greater the number of gears there are, the smoother the driving experience and the higher the fuel economy become.
Therefore, even if two cars are powered by the same engine, the car that has the transmission with the higher number of gears has better acceleration and fuel economy. The drawback, however, is that such a transmission is more complex, and thus, heavier.
Therefore, the central objective in transmission development is reducing size while increasing the number of gears.
The high-efficiency 6-speed automatic transmission in Sorento R and K7 (Cadenza) is significantly lighter and has fewer parts than the existing 5-speed transmission.
The 6-speed automatic transmission, which completed a 300,000 km durability test, is designed to minimize energy loss between gears and transmission shock.
In effect, it embodies the very best of Kia Motors’ transmission technology.
Our hybrid-specific continuously variable transmission (CVT) is designed to eliminate transmission shock and optimize fuel economy. Featuring a starter clutch and a high-efficiency oil pump, the hybrid CVT is 7% more fuel-efficient than existing automatic transmissions. We replaced the German-made transmission in the Pride (Rio) Hybrid with our own hybrid CVT, found also in the Forte LPi Hybrid. Our hybrid CVT has laid a solid foundation for the development of proprietary Kia technologies and raised cost competitiveness by replacing an imported component.

Technologies for going lightweight

Kia Motors is carrying out R&D toward the goal of making our cars 10% lighter than they currently are by 2015. A 10% reduction in weight results in enhancements of 3.2% in fuel economy, 8.5% in acceleration performance and 19% in steering wheel maneuverability. The vehicle also becomes 1.6 times more durable and emits 3.2% less CO2. To lighten the vehicle body, steel is replaced by aluminum alloy, resin and other lighter materials; the number of parts is reduced through the adoption of modules; and unnecessary weight is minimized through design optimization. Research into the use of lighter materials is focused on decreasing the thickness and weight of the materials while maintaining performance and durability.
In K7 (Cadenza), our effort to go lightweight begins with the wiring. Consisting of intelligent, electronic modules, the wires pass through the engine room and the interior of the vehicle in an optimized path. Moreover, an automotive structural adhesive is used instead of welding. As a result, K7 is one of the lightest vehicles in its class.
As for K5, its heating, ventilating, and air conditioning unit case is the first in Korea to be made of glass bubbles, a high-strength plastic. Polypropylene is generally the material of choice for embedded automotive components, but K5’s heating, ventilating, and air conditioning unit case is over 10% lighter than its polypropylene counterpart.
We plan to use glass bubble heating unit cases in newly released models. K5’s center pillar is made of ultra-high strength steel produced by hot stamping. Hot stamping is a method of reinforcing a given material by pressing it at a high temperature and then quickly cooling it. The ultrahigh strength steel making up K5’s center filler has reduced the number of parts and weight of K5 compared to its predecessor. It has also made the car strong and durable; K5 received the highest rating in a side-impact test.

Technologies for sustainability

Fuel economy regulations and policies are being strengthened around the world. The Korean government has decided to gradually lower average fuel economy and CO2 emissions ceilings to 17. 0km/ℓ and 140 g/km, respectively. The United States announced that it will strengthen its fuel economy standards for passenger cars and light trucks by 37% (37.8 mpg) and 25% (28.8 mpg), respectively, by 2016.
In the meantime, the EU decided to gradually lower the average CO2 emissions ceiling to 130 g/km, while China is considering toughening its fuel economy regulations by 14.5-22.4% from current levels by 2012. Kia Motors plans to meet Korea’s regulatory requirements by 2011, the United States’ by 2012-2013 and the EU’s by 2012. We are committed to realizing the kind of sustainability everyone can partake in through the downsizing technologies presented in this section and through technologies for future-oriented vehicles that will transform the paradigm of internal combustion engines.

Technologies for greater efficiency

ISG (Idle Stop & Go) ISG shuts down the engine when the car comes to a stop after having reached speeds of 8 km/h or higher. The engine immediately reignites when the car restarts. ISG raises fuel economy and cuts emissions by minimizing unnecessary fuel consumption by 10-15% on city roads, which demand stop-and-go driving.

Active Eco System The Active Eco System proactively controls parts of the engine, transmission and air condition system to realize optimal fuel economy. The Active Eco System raises fuel economy by minimizing fuel consumption from unnecessary acceleration, limiting the torque from rising when accelerating and optimizing the AC compressor’s duration of operation. Tests show that the Active Eco System enhances fuel economy by around 11%.

Eco Driving Point The Eco Driving Point system rates the fuel-economy status of a vehicle on a scale of 0 to 8. When the rating reaches 8, an image of a blooming flower appears on the dashboard. If the level-8 status is maintained for a set period of time, the flower turns into a bouquet. Eco driving points accumulate, so the driver can check just how fuel-efficient his/her driving is with this whimsical function.

Advanced Smart Cruise Control (ASCC) ASCC is the next-generation version of the existing radar-based cruise control function that helps maintain a safe distance with the vehicle ahead. ASCC goes a step further and even detects the stopping and restarting movements of the vehicle in front to automatically brake or restart the car. The car goes on automatic drive when the driver turns on the ASCC function, sets the desired speed and takes his/her foot off the accelerator. When ASCC detects a vehicle ahead, it activates the brake to maintain a safe distance. When the vehicle ahead stops or restarts, ASCC automatically stops and restarts the car accordingly.




Kia Sorento

“Highest Ranked Midsize SUV in Initial Quality in the U.S.”
- The Kia Sorento received the lowest number of problems per 100 vehicles among midsize suvs in the proprietary J.D. Power 2015 U.S. Initial Quality Study.SM Study based on responses from 84,367 new-vehicle owners, measuring 244 models and measures opinions after 90 days of ownership.  Proprietary study results are based on experiences and perceptions of owners surveyed in February-May 2015.  Your experiences may vary.  Visit

Kia Soul

“Highest Ranked Compact Multi-Purpose Vehicle in Initial Quality in the U.S.”
- The Kia Soul received the lowest number of problems per 100 vehicles among compact multi-purpose vehicles in the proprietary J.D. Power 2015 U.S. Initial Quality Study.SM Study based on responses from 84,367 new-vehicle owners, measuring 244 models and measures opinions after 90 days of ownership.  Proprietary study results are based on experiences and perceptions of owners surveyed in February-May 2015.  Your experiences may vary.  Visit

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