3 December 1998, Tokyo. Mitsubishi Motors announces that it has recently completed development of the new 4G15 1.5-liter in-line GDI engine, the smallest displacement engine of its type in the world. The 4G15 is the latest addition to the company's revolutionary GDI^*2 engine family that combines diesel-beating fuel economy with higher power outputs than conventional port-injection engines.

Mitsubishi Motors became the first automaker anywhere to apply GDI technology when, in August 1996, it launched the GALANT and LEGNUM models that were powered by the 4G93 in-line 1.8-liter GDI engine. This was followed by the 6G74 V6 3.5-liter unit in the PAJERO in April 1997, the 4G64 in-line 2.4-liter in the CHARIOT GRANDIS in October 1997, and other versions, bringing the number of Mitsubishi GDI-powered model series up to ten.

The new 4G15 power unit realizes 20% reductions in fuel consumption and global-warming CO2 emissions^*3, together with a 10% increase in power output^*4. This environmental-friendly engine will power the new SUW (Smart Utility Wagon) model due to be launched in January.

--------------------------------
*1: Smallest displacement engine to achieve stratified air supply and ultra-lean combustion by injection of gasoline directly into the cylinders.
*2: Gasoline Direct Injection, Mitsubishi Motors' direct injection engine.
*3: When used to power the new SUW model due to be launched in January 1999
*4: Compared with Mitsubishi current port-injection engine at normal operating speeds of under 2,500rpm

[ GDI is a trademark of Mitsubushi Motors ]

GDI in-line 1.5-liter engine profile

1. Development aims
   1. Class-topping economy (optimal tuning for unleaded regular gasoline)
   2. Higher power output at normal working speeds (flatter torque characteristics)
   
   
   
2. Mechanical features
   The principal GDI components that combine to give the new 4G15 engine its outstanding fuel economy and performance include:
   
   
   • Upright Straight Intake Port, which controls airflow into the cylinder;
   • Curved-crown Pistons, which control combustion behavior;
   • High-pressure Fuel Pump, which injects fuel directly into the cylinders at the high pressures required to achieve optimum lean burn characteristics;
   • High-pressure Swirl Injectors, which effectively and efficiently atomize and disperse the injection spray.

   A new compact, high-pressure fuel pump contributes to the more compact dimensions of the new engine.

   

G15 GDI specification

		4G15 GDI	Current 4G15
Bore x stroke (mm)		75.5 x 82.0	<--
Capacity (cc)		1468	<--
No. cylinders		4 in-line	<--
Valve train	Type	DOHC	<--
	No. Valves	Inlet x 2 / Exhaust x 2	<--
Compression ratio		11.0	9.5
Combustion chamber		Curved-crown	Flat top
Intake port		Upright	Standard
Preignition sensor		Yes	No
Fuel injection		Direct into cylinders	Port
Fuel feed pressure		50.0 kg/cm2	3.0 kg/cm2
Gasoline		Unleaded regular	<--