The Hyundai-Kia Theta (G4KC) is a gasoline 4-cylinder automobile engine
family. This is the third all-aluminum engine of Hyundai Motor Company
debuted in the fourth-generation Hyundai Sonata sedan(codenamed NF) and Kia
Optima (codenamed MG).
It features hollow stainless-steel DOHC with powder-metal cam lobes,
pent-roof combustion chamber and shimless bucket tappets in the cylinder
head. BorgWarner Morse TEC supplies the complete set of timing system that
uses the company's proprietary silent timing chains.
CVVT(Continuously-variable valve timing) works on the intake side.
The aluminum alloy engine block, which is formed using high-pressure
die-cast method, has a unique Metaldyne-supplied cassette-type balance
shaft module with a two-stage oil pump built-in. In the lower-end, the
block is reinforced by a ladder frame. Other notable features include
fracture-split sinter-forged connecting rods and stainless-steel exhaust
manifold.
Theta's EMS(engine management system) software is EMS-II from Siemens VDO
and the 32-bit PCM(Powertrain Control Module) calculates the amount of
intake air by utilizing a contamination-proof hot-film type MAF(mass air
flow) sensor.
Chrysler Corporation began production of a modified version of Theta,
dubbed World Engine, in Dundee, Michigan in October 2005. Chrysler
engineered their own air intake system and exhaust manifold which is made
of gray cast iron. The World Engine also differs in the EMS as it measures
the amount of intake air indirectly using a MAP sensor, another cost-saving
feature of the Chrysler-modified engine.
Hyundai Motor Manufacturing Alabama (HMMA) is currently building a Theta II
engine shop on the grounds of their Montgomery, Alabama automobile factory.
The shop will build only the Theta II engine for both the Hyundai plant and
the new Kia Plant in West Point, GA. It is scheduled to be completed by
August 2008.
The engine is used in:
HYUNDAI-KIA
Kia RONDO
Kia OPTIMA
Hyundai SONATA
Hyundai GENESIS COUPE 2.0
MITSUBISHI (4B1)
Mitsubishi LANCER
CHRYSLER
Dodge Caliber
Jeep Patriot 4x2
Jeep Compass 4x2
