The Lexus LFA is a two-seat exotic sports coupe produced by Lexus as a concept car, "halo" vehicle, racing prototype, and production model.[1] It is the second model in the F marque line of performance vehicles from Lexus, following the IS F. Three concept versions have been shown, each debuting at the North American International Auto Show with the LF-A designation as part of the LF Series concept line. The first LF-A concept premiered in 2005, followed in 2007 by a second LF-A with a more completely furnished interior and exterior. The third version of the LF-A, a roadster model, premiered in 2008. The production model, trademarked LFA,[2] was shown at the Tokyo Motor Show in October 2009.[3]
The production Lexus LFA features a new V10 engine and a carbon fiber-reinforced polymer (CFRP) body. CFRP materials account for 65 percent of the LFA's body composition by mass.[4] The LFA is scheduled to go into production in late 2010, with a projected run of 500 vehicles at an estimated base price of $US350,000-375,000.[5][6] A circuit-tuned variant is scheduled for 2012.
Development
2000–2004
In February 2000 the LF-A began development as a supercar project codenamed P280, which was intended to showcase the performance capabilities of Toyota Motor Corporation and its Lexus marque.[8][9] The first prototype was completed during June 2003. Prototypes of the LF-A were spotted regularly undergoing testing at Nürburgring since October 2004,[10] the famous motorsport race track in Nürburg, Germany.[11] Numerous test vehicles had been equipped with automatic retractable rear wings, and carbon ceramic brake discs.[12]
In January 2005, the first LF-A concept premiered at the North American International Auto Show in Detroit, Michigan as a design study with no plans for production. The first LF-A concept had an overall length of 173.2 inches (4,400 mm), five inches shorter than the Porsche 911 Turbo (996) while its wheelbase measured 101.6 inches (2,580 mm), or about nine inches longer.[13] The first LF-A was nearly 48 inches (1,200 mm) in height about equal to the Ferrari F430 with a width of 73.2 in (1,859 mm).[13] The concept name referred to Lexus Future-Advance.[14] The concept featured a glass roof and side cameras mounted in the side mirrors. Twin rear radiators were installed behind the rear wheels, and visible behind large screens. The rear bumper featured a triple exhaust placed in an inverted triangle formation. The wheels were shaped like turbines, and air-scoops were placed on the C-pilllars.[13] The overall design was the work of car stylists led by Lexus Design general manager Kengo Matsumoto.[9]
Following enthusiastic public reaction for the LF-A concept on the autoshow circuit, development continued with a greater emphasis on a possible production model.[15] The LF-A was reported to draw engineering resources from Formula One race car development, with Toyota along with Ferrari being the only companies producing their own F1 engines and chassis designs.[9] Concurrently, Lexus was preparing for the launch of its long-rumored F marque series of performance vehicles, with a production LF-A being a possible future member of this lineup. Reports in 2006 suggested that the LF-A concept car had received the green-light for production,[16] however these reports were not officially confirmed.[17] Development time was lengthened by the switch from an aluminum frame to a carbon fiber tub, the result of engineering efforts aimed at improving the LF-A's power-to-weight ratio.[8
In January 2007, a restyled LF-A concept car premiered alongside the first production F marque vehicle, the IS F sports sedan. The second LF-A concept featured a more aerodynamic exterior, a near-production interior, and F marque emblems. Later that year, Lexus GB director Steve Settle indicated plans for a V10 and hybrid version of the LF-A.[18] The hybrid version, combining a petrol engine with electric motors, would likely feature a V8 powertrain similar to that designed for the Lexus LS 600h L. LF-A test mules continued to be spotted at the Nürburgring, including early models with a large, fixed rear wing.[15] In December 2007, Auto Express reported that the LF-A had set an unofficial 7:24 lap record at the Nürburgring
In January 2008, Lexus displayed a roadster version of the LF-A concept car designated LF-A Roadster or LF-AR at the North American International Auto Show. Initial specifications for the roadster were a V10 engine under 5.0 L with over 500 hp (373 kW) and a top speed of over 200 mph (320 km/h).[21] Automotive photographers capturing the LF-A in various test guises had photographed a disguised drop-top test model, dubbed LF-A Spyder, on the Nürburgring as early as October 2005.[22] After its debut at the 2008 North American International Auto Show, the LF-A Roadster was also shown at the 2008 Pebble Beach Concours d'Elegance, the 2008 Geneva Motor Show, the United States Open Championship tournament, and at Lexus exhibits in Japan. Media reports uncovered a LFA trademark filing in December 2008, with the concept LF-A name dropping its hyphen to become LFA for the production model.
The second LF-A concepts had an overall length of 175.6 inches (4,460 mm), and a wheelbase of 102.3 inches (2,600 mm); height remained the same as the prior concept, while width grew to 74.6 inches (1,890 mm).[23] While the original LF-A had been strictly a concept model, the second concept's design reflecting engineering analysis for possible production.[24] Revised styling and improved aerodynamics were aimed at improving the coupe's overall top speed.[24] The reshaped exterior featured smoother lines with additional detailing, and more curved surfaces. The aft radiator cooling vents were retained, but integrated into the rear fascia, and the lower side and front air intakes were restyled, along with the forward fascia and headlamps.[15] The second LF-A concept and accompanying LF-A Roadster were also equipped with a retractable rear wing for improved handling at speed and a two-seat interior with a two-tone color scheme.
On August 5, 2009, Toyota's new CEO, Akio Toyoda, publicly confirmed production of the LF-A in his speech at a conference held at the Center for Automotive Research in the United States.[25] The production vehicles were expected to carry V10 engines,[26][27] putting the car in market competition with the Lamborghini Gallardo, Ferrari F430, the Porsche 911 (997), and the Chevrolet Corvette C6 ZR1. Pricing was estimated at over $225,000,[28] and close to $400,000.[29] In the same month, reports surfaced that coupe would be released as the LF-L to signify its appearances at Le Mans and to draw on its pre-production racing development.[30] Other possible names floated in the automotive press included the Lexus GT-F,[31] and Lexus SS550.[32] In September 2009, reports in Japanese automotive magazines indicated that the 4.8 L V10 engine for the LF-A would carry a 1LR designation.[33] A report in Evo in 2009 also indicated that the LF-A V10 engine was being considered for use in the upcoming Lotus Esprit
On October 21, 2009, the production Lexus LFA was unveiled on the first press day of the 41st biennial Tokyo Motor Show.[6] The vehicle was introduced by Akio Toyoda at a press conference, in which it was disclosed that the vehicle would be limited to 500 production copies. The vehicle carried the same designation as the concepts, LFA, but without the hyphen. The production designation reportedly stood for Lexus F-Series Apex.[35] The LFA was shown as the final vehicle of the press conference, following the LF-Ch hybrid concept. Pricing details at the show was estimated at $375,000.[6] Chief Engineer Haruhiko Tanahashi mentioned during the world's press at the Nürburgring in Germany that the LFA has lapped the Nürburgring Nordschleife in "better than 7 minutes 20 seconds", although no further specifics were given to the record lap. [36]
The production announcement for the LFA supercar marked the 20th anniversary of the launch of Lexus.[37] Given the high cost of construction and limited production, analysts do not expect LFA sales to be profitable.[6] However, the coupe is intended to serve as a testbed for new car technologies, including carbon fiber mass-production, and related performance vehicle development.[38] At its debut, a circuit-ready model was also indicated for 2012 release.
Engine
The Lexus LFA is powered by a 72° 4.8-liter V10 engine equipped with dual VVT-i carrying the 1LR-GUE designation with a maximum output of 560 PS (412 kW) delivered at 8,700 rpm. Its maximum torque output of 354 lb·ft (480 N·m) arrives at 6,800 rpm, 90 percent of which is available from 3,700 rpm. The engine redlines at 9,000 rpm, but with a fuel cutoff set at 9,500 rpm,[46] and is constructed using forged aluminum pistons, forged titanium connecting rods, and solid titanium valves. Dry sump lubrication prevents engine oil starvation through high speed corners and lowers the engine's center of mass. Air is fed directly from beneath the hood through a visible slit passing into a dual stage variable intake manifold and then into ten individual throttle bodies before finally exiting from a dual stage titanium muffler.
The LFA's engineers attempted to make the engine sound like that of a Formula One car with high revs, while at the same time maintaining typical Lexus reliability and vibration control. By selecting a V10 engine over an equivalent displacement V8 engine, reciprocating mass is reduced, allowing for more rapid engine response. Lexus claims their engine can rev from idle to its redline in 0.6 seconds and an analog tachometer needle could not accurately track the LFA's changes in engine speeds. This necessitated the use of digital tachometer which can instantly display engine speed.[47] The engine reportedly weighs less than the manufacturer's own 3.5-liter 2GR-FE V6 engine.
The powerplant gives the LFA a power-to-weight ratio of 5.9 lb/hp and enables it to reach a top speed of around 202 mph (325 km/h).[48] Like the IS F Yamaha co-developed the engine cylinder heads. The engine exceeds Euro V emissions. The engine is installed with a front mid-engine placement.[49] According to Chief Engineer Haruhiko Tanahashi a front engine layout was selected instead of a mid engine layout as it is inherently more forgiving dynamically, affording less experienced drivers a wider safety net
Transmission
The gearbox itself is a six-speed Automated Sequential Gearbox (electrohydraulic transmission) operated with paddle-shifters developed and constructed in-house by Toyota. The driver can select from four settings, auto, normal, sport and wet. In the sport mode, the manufacturer quotes minimum upshift times of 200 ms. According to Tanahashi a dual-clutch transmission was tested but the design team felt gear changes were overly smooth, resembling that of a traditional automatic and they preferred more abrupt and mechanically engaging shifts. However the auto mode and low speed performance suffer as a result.[51] A Torsen limited slip differential is also applied on the LFA,[3] and a launch control system is available.[42] The transmission gear ratios are as follows
Chassis
The Lexus LFA's frame is made from an in-house designed and manufactured carbon fiber-reinforced polymer (CFRP) center monocoque with aluminum front and rear subframes. The subframes, which can be removed and replaced minimizing potential repair costs, are joined to the monocoque using a newly developed aluminum flanged collar designed to create a stronger joint.[3] According to the manufacturer, the quality of the CRFP material matches that of aeronautical grades and is weaved by a laser monitored circular loom, one of only two in the world.[38] Overall 65% of the vehicle's total body mass is CFRP material while the remaining 35% is aluminum.[4] Manufacturer data indicates that the use of CFRP saves 100 kg (220 lbs) over equivalent aluminum materials.
An electric power steering rack with a 14.3:1 gear ratio is used. The front suspension utilizes a double-wishbone arrangement and there is a multi-link arrangement at the rear with coil-over dampers at all wheels. The dampers are a monotube design, each with a remote fluid reservoir that includes an expanding and contracting bellows, this is a purely mechanical system. The LFA further features six-piston front and four-piston rear Brembo monobloc brake calipers with 390 mm (15.4 in) front and 360 mm (14.2 in) rear carbon ceramic discs controlled by Toyota's Electronically Controlled Brake brake-by-wire system. Forged 20-inch BBS wheels fitted with 265 mm (10.4 in) front and 305 mm (12.0 in) rear Bridgestone next-generation Pontenza tires are standard
To maintain a near ideal weight distribution, a rear transaxle is used, in addition to the mounting of the fuel tank ahead of the rear axle and the radiators at the rear. The windshield washer fluid reservoir is mounted in the center next to the fuel tank to improve further the center of weight. Overall 48% of the LFA's mass is distributed along the front wheels with 52% at the rear.[53] The 73 liter fuel tank itself saddles the exhaust system keeping weight centered along the left-right axis. The engine is connected to the transaxle via a rigid carbon-fiber torque tube which the exhaust system runs directly below.[3] This stacked driveshaft and exhaust arrangement decreases the width of the center tunnel allowing for
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