Toyota AZ engine

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The Toyota AZ engine family is a straight-4 piston engine series. The AZ series uses an aluminum engine block with cast iron cylinder liners and aluminum DOHC cylinder heads. The engine series features many advanced technologies including slant-squish combustion chambers, offset cylinder and crank centers, and the VVT-i continuously variable intake valve timing system. The aluminum engine measures 626-mm (25-in) long, 608-mm (24-in) wide, and 681-mm (27-in) tall.

The cylinder block is an open-deck, midi-skirt die-cast aluminum type with cast-in iron liners and a die-cast aluminum lower crankcase and a stamped oil pan. The forged steel crankshaft is fully balanced with eight counterweights and supported by five main bearings. A helical gear pressed in No. 3 counterweight drives twin contra-rotating balance shafts in the shaft housing within the lower crankcase.

The dual overhead camshafts are driven by a single-stage roller chain of 8.0-mm (0.3-in) pitch, enabling a narrow included valve angle of 27.5°. The camshafts act on four valves per cylinder via bucket tappets. As in the recent Toyota engine practice, no clearance adjusting shim is employed. Valve diameters are 34.0 mm (1.3 in) for intake and 29.5 mm (1.2 in) for exhaust, with 8.0-mm (0.3-in) lift for both intake and exhaust. The four-vane VVT-i device is fitted on the intake camshaft, altering timing by 50°.

Fuel is injected sequentially via an ultra-fine-atomization injector with twelve small injection holes, each 0.18 mm (0.01 in) in diameter. As in the smaller NZ engine, the new AZ adopts a plastic, built-up, and vibration-welded intake manifold integrating a large volume plenum chamber (3.5-L (214 in3) volume including a 1.3-L (79 in3) resonator).

1 1AZ-FSE
2 2AZ-FE
3 2AZ-FXE
4 See also

[edit] 1AZ-FSE

The 1AZ-FSE is a 2.0 L (1998 cc) version. Bore is 86.0 mm and stroke is 86.0 mm. Output is 155 hp (114 kW) at 6000 RPM with 145 ft·lbf (192 N·m) of torque at 4000 RPM. The 1AZ-FSE features Toyota's D-4 direct injection system.

Applications:

[edit] 2AZ-FE

The 2AZ-FE is a 2.4 L (2362 cc) version built in Georgetown, KYobtains a total displacement of 2362 cm3 with 88.5-mm (3.5-in) bore and 96.0-mm (3.8-in) stroke, resulting in a compression ratio of 9.6:1. Output is 157 hp (117 kW) at 5600 RPM with 162 ft·lbf (220 N·m) of torque at 4000 RPM. The 2AZ-FE also has one-piece cast camshafts. Output for the 2007 Toyota Camry is 158hp and 161 lft lbs of torque. There is also a version of the 2AZ-FE engine with 160 hp and 163 ft lbs of tourqe made in Japan for the Scion tC.

Applications:

Toyota Camry
Toyota Camry Solara
Toyota RAV4
Toyota Highlander/Kluger
Toyota Estima / Toyota Previa / Toyota Tarago
Toyota Alphard
Toyota Blade
Scion tC

The 2007 Toyota RAV4 produces 166 hp (123 kW) at 6000 RPM and 165 ft·lbf of torque at 4000 RPM ^[1].

[edit] 2AZ-FXE

The 2AZ-FXE is a variant of the 2AZ-FE. It has the same bore and stroke, but has a higher physical compression ratio of 12.5:1, and the inlet valve closing is retarded. The net result is that the engine has a greater effective expansion than compression – making it Atkinson cycle, rather than the conventional Otto cycle.

The reduction in cylinder charge means reduced torque and power output, but efficiency is increased. This combination makes the 2AZ-FXE suitable for use in hybrid vehicles, where peak torque and power demands can be met by the electric motor and battery.

Maximum output when used in the Camry is 147 hp (108 kW) at 6000 RPM with 138 ft·lbf (187 N·m) of torque at 4400 RPM.

Applications: