|Manufacturer||Toyota Motor Corporation|
|Configuration||DOHC 90° V8|
|Predecessor||Toyota V engine|
|Successor||Toyota UR engine|
The Toyota UZ engine family is a 32-valve quad-camshaft V8 piston engine series used in Toyota's luxury offerings and sport utility vehicles. Three basic versions have been produced, the 1UZ-FE, 2UZ-FE, and 3UZ-FE. The UZ series was mostly replaced by the UR series but the 3UZ-FE continues to be produced for the current model Crown Majesta 4WD (Japanese market only).
The 4.0 L (3,969 cc or 242.2 cu in) all-alloy 1UZ-FE debuted in 1989 in the first generation Lexus LS 400/Toyota Celsior and the engine was progressively released across a number of other models in the Toyota/Lexus range. The engine is oversquare by design, with a bore size of 87.5 mm (3.44 in) and stroke of 82.5 mm (3.25 in). It has proved to be a strong, reliable and smooth powerplant with features such as 6-bolt main bearings and belt-driven quad-camshafts. The water pump is also driven by the cam belt. The connecting rods and crankshaft are constructed of steel. The pistons are hypereutectic.
Its resemblance to a race engine platform (6 bolt cross mains and over square configuration) was confirmed in 2007 by David Currier (in an interview with v-eight.com), vice president of TRD USA, stating that the 1UZ platform was based on CART/IRL engine design. It was planned to be used on GT500 vehicles, however its subsequent use in the Daytona Prototype use was not planned.
In its standard, original trim with 10:1 compression, power output is 191 kW (256 hp), torque of 353 N·m (260 lb·ft).
The engine was slightly revised in 1995 with lighter connecting rods and pistons and an increased compression ratio to 10.4:1 resulting in peak power of 195 kW (261 hp) and torque of 363 N·m (268 lb·ft).
In 1997, Toyota's VVT-i variable valve timing technology was introduced along with a further compression ratio increase to 10.5:1, bumping power and torque to 216 kW (290 hp) and 407 N·m (300 lb·ft). In the GS400 application, output was rated at 300 hp and 310 lb·ft of torque.
The 1UZ-FE was voted to the Ward's 10 Best Engines list for 1998 through 2000.
The 2UZ-FE was a 4.7 L (4,664 cc or 284.6 cu in) version built in Tahara, Aichi, Japan and at Toyota Motor Manufacturing Alabama. Unlike its other UZ counterparts, this version uses a cast iron block to increase durability, as it was designed for low-reving, high-torque pickup and SUV applications. Its bore is 94 mm (3.7 in) and stroke is 84 mm (3.3 in).Output varies by implementation, but one VVT-i variant produces 202 kW (271 hp) at 4800 rpm with 427 N·m (315 lbf·ft) of torque at 3400 rpm. JDM versions produce 173 kW (232 hp) at 4800 rpm and 422 N·m (311 lbf·ft) at 3600 rpm, while Australian models produce 170 kW (230 hp) at 4800 rpm and 410 N·m (300 lbf·ft) at 3600 rpm.
Like the 1UZ-FE it has aluminum DOHC cylinder heads, MFI fuel injection, 4 valves per cylinder with bucket tappets, one-piece cast camshafts, and a cast aluminum intake manifold. For 2010, it was replaced by the 1UR-FE or 3UR-FE, depending on the country.
Toyota Racing Development offered a bolt-on supercharger kit for the 2000–2003 Tundra and the 2003 GX 470.
Another 2UZ-FE variation adds VVT-i and electronic throttle control.
The 3UZ-FE, is a 4.3 L (4,292 cc or 261.9 cu in) version built in Japan. Bore is 91 mm (3.6 in) and stroke is 82.5 mm (3.25 in). Output is 216 to 224 kW (290 to 300 hp) at 5600 rpm with 441 N·m (325 lb·ft) of torque at 3400 rpm. It has an aluminum engine block and aluminum DOHC cylinder heads. It uses SEFI fuel injection, has 4 valves per cylinder with VVT-i. In 2003, the engine was linked to a six-speed automatic in applications with improved fuel efficiency.
A 4.4L version replaced the 3S-GTE as the engine used in Toyota's 500 hp (370 kW) Super GT race cars up to 2009and a 5.0L version was used in the Grand American Road Racing (Grand Am) Series.
In 1997, the US Federal Aviation Administration granted production certification for the FV2400-2TC, a twin-turbocharged airplane powerplant based on the UZ series Lexus engine. The 360 hp (270 kW) FV2400 was developed in partnership with Hamilton Standard, which provided the digital engine-control system. The goal was to produce a four-seat propeller aircraft.
In 1998, a marine derivative of the UZ powerplant was produced for boating applications. The 4.0 L VT300i engine, producing 300 hp (220 kW) at 6000 rpm and 310 lbf·ft (420 N·m) at 4200 rpm, used the same block as the UZ engine on the Lexus SC 400, GS 400, and LS 400. The marine engine was used on the Toyota Epic waterski boat.