Bác nào biết thì giải đáp thắc mắc này hộ em với, tại sao trên 1 số xe như lexus LS 460 lại dùng kết hợp cả phun trực tiếp và phun gián tiếp mà ko chỉ dùng một loại duy nhất là phun trực tiếp thôi? Lợi ích của việc này là gì?
Có không đó chú, theo dưới đây thì nó chỉ có 1 loại kiểu phun thôi, sao lại ôm cả 2 kiểu phun được???
Đã tận mắt thấy, tay sờ chưa?
1UR-FSE[edit]
1UR-FSE
The
1UR-FSE V8 engine, introduced with the Lexus LS 460 & LS 460 L luxury sedans in 2006 has a 4.6 liter (4608cc) displacement, which it gets from a 94 mm
bore and 83 mm
stroke. The engine includes D4-S direct injection and dual
VVT-iE producing 385 hp (287 kW) at 6,400 rpm and 51 kg·m (500 N·m; 369 lb·ft) at 4,100 rpm.
1UR-FSE undergoes
X-ray inspection and a CT (
computed tomography) scan to ensure minimal deformation after the die-casting process. Camshafts are hollow to minimize weight.
[2]
Applications:
1UR-FE[edit]
The
1UR-FE is based on the 1UR-FSE
but lacks the D4-S direct injection technology. Originally used for Lexuses in the Middle East, it was introduced in 2010 in other markets to replace the 2UZ-FE engine in truck and SUV applications. This engine produces 347 hp (259 kW) at 6,400 rpm and 46.9 kg·m (460 N·m; 339 lb·ft) at 4,100 rpm in the Lexus GS and LS. For the Toyota Land Cruiser the engine produces 304 hp (227 kW) at 5,500 rpm and 44.8 kg·m (439 N·m; 324 lb·ft) at 3,400 rpm.
Applications:
Sr, nó bên dưới đây:
Tuning up an early generation FSI power plant to generate higher power is difficult, since the only time it is possible to inject fuel is during the induction phase. Conventional injection engines can inject throughout the
4-stroke sequence, as the injector squirts onto the back of a closed valve. A direct injection engine, where the injector injects directly into the cylinder, is limited to the intake stroke of the piston. As the RPM increases, the time available to inject fuel decreases. Newer FSI systems that have sufficient fuel pressure to inject even late in compression phase do not suffer to the same extent; however, they still do not inject during the exhaust cycle (they could but it would just waste fuel). Hence, all other factors being equal, an FSI engine needs higher-capacity injectors to achieve the same power as a conventional engine.
Some engines overcome this limitation by using both direct injection and multiport fuel injection (Toyota 2GR-FSE V6).
Đọc chỗ này sẽ hiêủ vì sao họ ôm cả twin injection
2GR-FSE[edit]
2GR-FSE engine in the 2008 Crown
The 2GR-FSE is a 3.5L engine used in the Lexus IS, GS 350, Mark X and Crown incorporate Toyota's latest D4-S twin injection fuel system. This system combines direct injection(949cc/min injectors) with traditional port injection (298cc/min injectors). Direct injection lowers the tendency to knock (detonation) and increases performance by reducing the charge intake temperature. Traditionally direct injection engines require an in engine mechanism such as swirl ports or specific piston crown shapes to increase tumble in the engine. These are in place to help achieve a homogeneous air-fuel mixture inside the cylinder at low rpm and high load, these mechanisms inhibit performance at higher rpm. In the 2GR-FSE the port injection is used considerably to achieve the correct mixture without having in engine restrictions, meaning the engine achieves specific power near the top of all naturally aspirated production gasoline engines in the world (67kW/L, 235kW in the Mark X). Toyota also developed a new type of injector for this engine. The dual fan spray pattern of the direct injectors is perpendicular to the piston travel with wide dispersion in the cylinder helping improve in cylinder mixing and therefore power and efficiency. The port injectors not only help improve the power and efficiency but they also help improve emissions especially in the first 20 seconds after start up (when the catalytic converter is in its warm up stage). Development of V-6 3.5-liter Engine Adopting New Direct Injection System