It was the 1955 Crown that launched Toyota Motor Co. as a proper passenger car manufacturer. Prior to this model, Toyota had supplied essentially light-truck chassis, on which specialist suppliers mounted crude hand-formed bodies, and sold them as Toyopets largely to fleet users. Toyota's major Japanese competitors at the time were producing passenger car models under license, which included Nissan's Austin, Isuzu's Hilman, Hino's Renault 4CV, and Mitsubishi Heavy Industries' Kaiser J.
Eiji Toyoda, retired chairman of Toyota, was de facto chief engineer in those early days. He confided that it was not Toyota's nationalistic obstinacy that prompted the design and development of the Crown. The budding company simply could not afford the complications of having the Crown and a collaborative project offered by a foreign manufacturer, such as VW. The Crown, being developed under the stewardship of the late and legendary project engineer Kenya Nakamura, showed promise.
The Crown crossed the Pacific in 1957, only to discover America's vast land and fast traffic too arduous for a compact sedan powered by a modest pushrod 1.5-L engine. Eiji Toyodta decided on a hasty retreat from the American market to revisit the company's passenger car efforts. This crown prince of Toyota cars has since stayed home for 10 generations, to grow in size and sales volume, attracting the affluent Japanese.
The 11th generation Crown is aimed exclusively at the Japanese market. The range's two series, the Royal and the upscale Majesta, has been joined by a third line called Athlete, a sporty version of the former. The Royal/Athlete is on the shorter version of Toyota's front-engine, rear-wheel-drive platform on a 2780-mm (109-in) wheelbase shared with the Japan-only Progres. The Majesta's platform is shared with the Lexus GS300/400; however, its wheelbase has been stretched to 2800 mm (110 in). Their respective unit-body architectures are new, brought up to the latest Toyota global outstanding assessment (GOA) standards, meeting the crash requirements of Europe, the U.S., and Japan. The body's torsional rigidity has been improved by 25%. The sedan's 0.29 drag coefficient is achieved by the addition of fairings ahead of the front and rear wheels, a flat underfloor covering, and a rounded under-nose section.
The Royal/Athlete is 4820 mm (190 in) long, 1765 mm (69 in) wide, and 1495 mm (59 in) tall, with masses ranging from 1815 to 1875 kg (4000 to 4134 lb). The Majesta measures 4900 mm (193 in) long, 1795 mm (71 in) wide, and 1455 mm (57 in) tall, and mass ranges between 1660 and 1780 kg (3660 and 3924 lb).
The rear-wheel-drive Royal/Athlete's engine center has been pushed back by 40 mm (1.6 in), and the Majesta's by 50 mm (2 in). The 70-L (18.5-gal) fuel tank has been relocated from behind the rear seat to under it, gathering a larger mechanical mass within the wheelbase for improved dynamics. (All-wheel-drive models' engine positions are unchanged.) Interior dimensions have been increased in all directions, the Royal/Athlete's cabin length gaining 40 mm (1.6 in) and the Majesta's 20 mm (0.8 in), while the luggage volume is enlarged to 530 L (18.7 ft3) within the same overall length as their predecessors—no mean feat for Toyota's packaging engineers.
The chassis features all independent suspension. The front suspension is by "double wishbones," with a high-mounted upper arm. At the rear, an upper L-arm, lower twin unequal-length splayed transverse links and a toe-control link form the double wishbones. The top-of-the Royal-series model is equipped with a sophisticated electronically controlled, variable shock absorber system called H-°° TEMS (the symbol standing for an advanced control logic from Hardy-Infinity and TEMS for Toyota electronically modulated suspension). The top Majesta features an electronically controlled pneumatic spring system, combined with the TEMS, centrally controlled by the nonlinear H-°° logic. The Majesta's semi-active suspension functions as if there are two hypothetical shock absorbers on the car's outboard side, exercising precise control of roll and bounce and maintaining an even keel.
The top V8-powered Majesta model is fitted with active rear-wheel-steering (ARS) – an electronically controlled, electrically actuated system that supports the driver by stabilizing the vehicle's behavior in a sudden maneuver. It induces understeer behavior by steering the rear wheels in the same direction as the front.
The range's mainstream powertrain is Toyota's JZ inline six-cylinder engine family. The 1JZ-GE is a naturally aspirated DOHC 2491-cm3 unit with VVT-i (intelligent variable intake valve timing) and 24 valves rated at 147 kW (200 hp) at 6000 rpm and 255 N•m (188 lb•ft) at 4000 rpm. This engine powers both the rear- and all-wheel-drive Royal/Athlete. Next up the power ladder is the type 2JZ-GE 2997-cm3 version for the all-wheel-drive Royal, producing 162 kW (220 hp) at 5800 rpm and 294 N•m (217 lb•ft) at 3800 rpm. The performance Athlete is powered by a turbocharged version of the 1JZ 2.5-liter unit with a GTE suffix, putting out 206 kW (280 hp) at 6200 rpm and 378 N•m (279 lb•ft) at 3800 rpm.
A significant addition to the JZ family of engines is the 2JZ-FSE, a DOHC 24-valve 3.0-L unit, which is Toyota's second D4 direct-injection gasoline engine. As its designation indicates, it shares its lower half with the 2997-cm3 2JZ-GE unit with 86.0-mm (3.39-in) bore and stroke. The D4 upper half is unique to this engine, and represents the state of Toyota's direct-injection art. The 2JZ-FSE's power and torque outputs are the same as the port-injection 2JZ-GE's at 162 kW (220 hp) and 294 N•m (217 lb•ft), but at lower engine speeds of 5600 rpm and 3600 rpm, respectively. The engine's compression ratio is a higher 11.3:1 vs. the port injection unit's 10.5:1, with both engines using regular-grade unleaded gasoline.
The original D4 3S-FSE 2.0-L I4 engine burns an ultra-lean mixture (as lean as a 50:1 air/fuel ratio) in a stratified-charge combustion zone. The new 2JZ-FSE does not take the lean-burn envelope that far, operating at an air/fuel ratio ranging from 20:1 to 40:1. In this zone, fuel is injected in the latter part of the engine's compression stroke by the new high-pressure slit-nozzle injector. Fuel mist forms a stable, combustible mixture (closer to the stoichiometric air/fuel ratio) stratum around the spark plug. The flame propagates to the ultra-lean mixtures around this stratum. The overall air/fuel ratio can be as lean as 40:1.
The new 2JZ-FSE's stratified charge combustion envelope has been extended to a higher vehicle speed range of about 120 km/h, adequately covering Japan's real-life highway cruising. Fuel economy, quoted at 11.4 km/L (27 mpg) on Japan's urban 10/15 mode for the Royal, is about 21% superior to the previous port-injection model. At high-load conditions such as rapid acceleration and high-speed running, the engine operates in the stoichiometric zone with fuel injected during the intake stroke. One of the two straight intake ports is fitted with a flow-control valve, its opening and closing improving cylinder filling and combustion efficiency. During low-speed, high-load operation, this valve is fully closed, with the air admitted through the single open port, accelerating flow speed and improving cylinder filling. The flow-control valve is fully opened during high-speed, high-load operation, introducing ample air. A transient "weak stratified charge" zone, with an air/fuel ratio of 18:1 through 25:1, ensures a smooth transition between ultra-lean stratified-charge operation and homogeneous-charge combustion. Fuel is "split-injected" partially during the intake stroke and the remainder during the compression stroke.
The first-generation D4 engine relies heavily on a powerful air-swirl motion generated by two different port shapes for each cylinder: a helical port with a small protrusion just before the intake valve opening and a straight port, the latter fitted with a swirl-control valve. During ultra-lean operation, this valve is closed, letting the air in from the helical port. Combined with the intricately shaped, asymmetrical deep-bowl piston, a combustible mixture strata is formed around the spark plug.
The new D4's ports are both straight, relying less on the air's swirl motion, and the piston's asymmetrical deep cavity is an elongated shape versus the original D4's heart-shaped cavity. The high-pressure plunger-type fuel injection pump is driven by the exhaust camshaft. It generates pressures between 8 and 13 MPa (1160 and 1890 psi).
The new D4 employs a new "slit nozzle" injector. It has a single slit-like hole, an arched slit of only 0.16-mm (0.006-in) width. The slit nozzle injector fans out highly pressurized fuel spray, which forms a stable mist stratum around the spark plug without the aid of air turbulence. A cold-start injector feeds fuel into the plenum chamber to aid startability.
A single stage cogged belt drives the exhaust camshaft. The exhaust camshaft carries a vane-type VVT-i continuously variable intake valve timing device and drives the intake camshaft via a split and spring-loaded "scissors" geartrain. The VVT-i has a variable timing range of 40°. The camshaft acts on valves via shimless bucket tappets. The intake and exhaust valves are inclined at a narrow included angle of 22.6°, vs. the port-injected 2JZ-GE's 45°. Valve diameters are 33.5 mm (1.32 in) for intake and 28.0 mm (1.10 in) for exhaust vs. the 2JZ-GE's 33.5 mm (1.32 in) and 29 mm (1.14 in), respectively. Lifts are 6.0 mm (0.24 in) for either engine type. The induction system employs a variable-length ACIS (acoustic control induction system) to exploit the incoming air's pulsation to obtain inertia charge effect.
The top-of-the-series Majesta shares its 1UZ-FE 4.0-liter V8 engine with quad camshafts and 32 valves with the Lexus LS/GS400. This engine produces 206 kW (280 hp) at 6000 rpm and 402 N•m (296 lb•ft) at 4000 rpm. Toyota's "smart" five-speed automatic is offered in all models except the Royal 2.5 and all-wheel-drive models, which are equipped with a four-speed unit. The Athlete's automatic can be manually shifted by push buttons on the steering wheel spokes. Optional equipment includes a DVD navigation system and an adaptive cruise control employing laser radar (with no brake intervention).
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