4GR-FSE Engine

4GR-FSE ENGINE

Description

The newly developed 4GR-FSE D-4 (Direct injection 4-stroke gasoline engine) is a 2.5-liter, 24-valve DOHC V6 engine. This engine uses a Direct injection system, Dual VVT-i (Variable Valve Timing-intelligent) system, DIS (Direct Ignition System), ACIS (Acoustic Control Induction System), Electronic SCV (Swirl Control Valve) and ETCS-i (Electronic Throttle Control System-intelligent). These control functions achieve improved engine performance, fuel economy, and clean emissions.

4GR-FSE  Description

4GR-FSE ENGINE Description

Engine Specification

4GR-FSE Engine Specification

*1: Similar high quality ethylene glycol based non-silicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid organic acid technology. (Coolant with hybrid organic acid technology consists of a combination of low phosphates and organic acids.)

*2: Weight shows the figure with the oil and engine coolant fully filled.

Valve Timing

4GR-FSE Engine Valve Timing

4GR-FSE Engine Valve Timing. Diagram

Reference

 

D-4 (Direct injection 4-stroke gasoline engine) System

 

  • An engine equipped with a D-4 system has the injector installed on the combustion chamber, which injects the fuel pressurized in the fuel pump (high pressure) directly into the combustion chamber. Due to the injection directly in the cylinder, it is possible to increase the compression ratio. It is possible to increase the compression ratio due to direct injection taking advantage of the “latent heat of vaporization*” of the fuel. This principle results in a cooling effect on the compressed mixture. The lower temperature of the compressed mixture reduces the tendency of the mixture to detonate or preignite in the engine. The increased compression ratio of the engine results in improved power output.
  • A conventional gasoline EFI engine has the injector installed in the intake port and the air and fuel injected inside the intake port are drawn into the cylinder by the intake stroke of the piston.
  • In the D-4 system, a slit nozzle type injector precisely controls the quantity of the high pressure fuel and produces a fine-grain atomization to thus improve the fuel efficiency.

* Latent heat of vaporization is an effect that results in a temperature drop when a liquid changes from a liquid to a gas. An example is the cooling effect produced when alcohol evaporates from skin, or when liquid refrigerant changes to a gas.

D-4 (Direct injection 4-stroke gasoline engine) System

D Depending on the driving conditions, by injecting the fuel at an optimal time during the intake stroke, an equal air-fuel mixture (homogenous mixture) is produced.

When the engine is cold, fuel is injected at the end of the compression stroke. Due to the combustion time being lengthened by providing a leaner mixture, the exhaust temperature is raised to accelerate engine and catalyst warm-up. Catalysts that are warmed up earlier accelerate exhaust emission purification.