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| Manufacturer | Lexus |
|---|---|
| Parent company | Toyota Motor Corporation |
| Also called | Lexus LF-A (concept) |
| Production | Dec 2010 – Dec 2012 (500 total, 20 monthly) |
| Assembly | Motomachi, Toyota City, Japan |
| Class | Sports car Racing car |
| Body style(s) | 2-door coupé 2-door roadster |
| Layout | Front-mid-engine, rear-mid-transaxle |
| Engine(s) | 4.8 L 1LR-GUE V10 |
| Transmission(s) | 6-speed Automated Sequential Gearbox |
| Wheelbase | 2,605 mm (102.6 in) |
| Length | 4,505 mm (177.4 in) |
| Width | 1,895 mm (74.6 in) |
| Height | 1,220 mm (48 in) |
| Curb weight | 3263-3483 lbs |
| Designer | Haruhiko Tanahashi |
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. The use of CFRP materials, which account for 65 percent of the LFA's body composition,[4] is to reduce overall weight for improved performance. The LFA is scheduled to go into production in late 2010, with a projected run of 500 hand-built vehicles at an estimated base price of $US350,000-375,000.[5][6] A circuit-tuned variant is scheduled for 2012.[7]
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[edit] Development
[edit] 2005–2006
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] 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. However, prototypes of the LF-A had been spotted regularly undergoing testing at Nürburgring since October 2004,[9] the famous motorsport race track in Nürburg, Germany.[10] Numerous test vehicles had been equipped with automatic retractable rear wings, and carbon ceramic brake discs.[11]
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.[12] 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).[12] The concept name referred to Lexus Future-Advance.[13] 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.[12] The overall design was the work of car stylists led by Lexus Design general manager Kengo Matsumoto.[8]
Following enthusiastic public reaction for the LF-A concept on the autoshow circuit, development continued with a greater emphasis on a possible production model.[14] The LF-A was reported to draw engineering resources from Formula 1 race car development, with Toyota along with Ferrari being the only companies producing their own F1 engines and chassis designs.[8] 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,[15] however these reports were not officially confirmed.[16]
[edit] 2007–2008
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.[17] 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.[14] In December 2007, Auto Express reported that the LF-A had set an unofficial 7:24 lap record at the Nürburgring.[18][19]
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).[20] 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.[21] 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.[2]
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).[22] While the original LF-A had been strictly a concept model, the second concept's design reflecting engineering analysis for possible production.[23] Revised styling and improved aerodynamics were aimed at improving the coupe's overall top speed.[23] 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.[14] 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.
[edit] 2009
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.[24] The production vehicles were expected to carry V10 engines,[25][26] 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,[27] and close to $400,000.[28] 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.[29] Other possible names floated in the automotive press included the Lexus GT-F,[30] and Lexus SS550.[31] 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.[32] A report in Evo in 2009 also indicated that the LF-A V10 engine was being considered for use in the upcoming Lotus Esprit.[33]
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.[34] 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]
The production announcement for the LFA supercar marked the 20th anniversary of the launch of Lexus.[35] 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.[36] At its debut, a circuit-ready model was also indicated for 2012 release.[37]
[edit] Production
Lexus began taking orders for the LFA supercar on October 23, 2009. Buyers will be selectively chosen by Lexus in the second quarter of 2010.[38] Production will begin in December 2010 as a 2011 model. Only 500 total LFA models will be made worldwide, with only 20 produced each month. Each car will be custom ordered to the customer's specifications, and will cost an estimated $350,000 - $375,000 USD, depending on options and customization.[39]
Following the LFA's release at the Tokyo Motor Show, Lexus unveiled a website with a 'LFA configurator' which allowed users to select exterior and interior colors, brake caliper colors, seats, steering wheel leather, and other interior designs.[40][41] In total, there are over 30 billion possible configurations.[41] Each LFA will be hand-built by a dedicated production team of engineers and specialists at Toyota's Motomatchi plant in Aichi, Japan.[42]
During LFA production, each vehicle will receive a plaque which is individually numbered, indicating the unit's place in the production run. Each LFA V10 engine will also bear the signature of the specialist who assembled it.[42] With 20 units produced monthly, production of the entire LFA run will last from December 2010 to December 2012.
[edit] Overview
[edit] 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 552 bhp (412 kW) delivered at 8700 rpm. Its maximum torque output of 354 lb-ft arrives at 6800 rpm, 90 percent of which is available from 3700 rpm. The engine, like the Ferrari 458 Italia, redlines at 9000 rpm, but with a fuel cutoff set at 9500 rpm[43] 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 reduces the engine's center of gravity. Air is fed directly from beneath the hood through a visible slit passing into a dual stage variable intake manifold and then into 10 individual throttle bodies before finally exiting from a dual stage titanium muffler.
The LFA's engineers attempted to make the engine to sound like that of a Formula One car with rapid 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 tach which can instantly display rpms. The engine reportedly weighs less than the manufacturer's own 3.5-liter 2GR-FE V6 engine.
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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).[44] Like the IS F Yamaha co-developed the engine cylinder heads. The engine complies with Euro V emissions. On the LF-A, the V10 is installed with a front mid-engine placement.[45] 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 with a wider safety net.[46]
[edit] 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 preferred more abrupt and mechanically engaging shifts. However the auto mode and low speed performance suffer as a result.[47] A Torsen limited slip differential is also applied on the LFA,[3] and a launch control system is available.[41] The transmission gear ratios are as follows:[48]
| Gear | 1 | 2 | 3 | 4 | 5 | 6 | Reverse | Final Drive |
|---|---|---|---|---|---|---|---|---|
| Ratio | 3.231 | 2.188 | 1.609 | 1.233 | 0.970 | 0.795 | 3.587 | 3.417 |
[edit] 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 two in the world.[36] Overall 65% of the vehicle's total body mass is comprised of 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 while the front suspension utilizes a double-wishbone arrangement, and a multi-link arrangement at the rear with coil-over dampers at all wheels. The dampers are a fixed monotube design. 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.[45]
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. Overall 48% of the LFA's mass is distributed along the front wheels with 52% at the rear.[49] 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 centrally located seating.
[edit] Exterior
The production Lexus LFA has an overall length of 177.4 inches (4,510 mm), while its wheelbase measures 102.6 inches (2,610 mm), with a height of 48 inches (1,200 mm) and width of 74.6 in (1,895 mm).[48] Compared to the prior 2007–2008 concepts, the production model is nearly 2 inches (51 mm) inches longer, with identical width, height, and nearly same wheelbase dimensions.
The LFA body features sharp edges and cutoffs for improved aerodynamic performance, made possible by the carbon fiber body.[38] The body was designed with an emphasis on downforce. There are air scoops located over the rear fenders which feed the aft-mounted radiators. The speed-sensitive rear wing incorporates a Gurney flap and deploys at speeds over 50 mph.[38] With the wing retracted the LFA's body has a drag coefficient of Cd 0.31.[38]
[edit] Interior
The LFA interior incorporates carbon fiber, leather, alcantara, and metallic surfaces. There are two bucket seats, and Lexus' Remote Touch controller interface. The instrument display is a digital speedometer with color-changing background, size-changing numbers, and side-appearing submenus.[38] The LFA features a new driver and passenger seat-belt airbag design[38] increases similar to the S-Class ESF safety concept car. The steering wheel feaures a right-mounted start button, and alloy paddle-shifters.[38] A 12-speaker Mark Levinson sound system with compact lightweight components was also developed for the interior.[50]
[edit] Performance
Official preliminary specifications for the Lexus LFA are as follows:[48]
| Engine type | 1LR-GUE 72° V10 | Transmission | 6-speed ASG |
|---|---|---|---|
| Valvetrain | DOHC 4-valves/cylinder, dual VVT-i | Redline | 9000 rpm (rev limiter 9500 rpm) |
| Displacement | 4,805 cc (293.2 cu in) | Curb weight | 1,480 kg (3,263 lb) |
| Bore x Stroke | 88 mm × 99 mm (3.5 in × 3.9 in) | Power-to-weight | 5.9 lb/hp |
| Compression Ratio | 12.0:1 | 0-100 km/h (62 mph) | 3.7 sec.[48] |
| Power | 412 kW (560.2 PS; 552.5 hp) @ 8700 rpm | 0-60 mph (97 km/h) | 3.6 sec.[35] (w/o launch control)[41] |
| Torque | 480 N·m (354.0 ft·lbf) @ 6800 rpm | Top speed | 325 km/h (202 mph)[48] |
[edit] Motorsport
[edit] 2008
A Lexus LF-A prototype was entered on 10 May 2008 on the Nürburgring 4 hour VLN endurance race where it surprisingly won the engine close-to-production SP8 class[51] with 6 entrants, as all others, including a Porsche 997 Turbo and Aston Martin Vantage, failed to finish. The best lap time on the 24,4 km version was 9:06;[51] by comparison, the SP7 class Porsche GT3-RSR, which did not finish the race, had a fastest lap of 8:44;[51] the LF-A's time was about on par with Cup-GT3. This resulted in finishing 77th[52] overall among over 200 teams.
Lexus also took part in the 24 Hours Nürburgring[53] on 24/25 May 2008, with four Japanese drivers including Akira Iida leading the team. The LF-A was involved in a crash just prior to the race and was hurriedly repaired in two hours to make the race.[54] As car #14, [55] it qualified 27th[56] among 223 cars, and finished 7th in the SP8 class of 11 entrants, and 121st overall, with a best lap average speed of 163 km/h (101 mph), compared to 175 km/h (109 mph) of the fastest cars.
[edit] 2009
On 4 April 2009, a LF-A and a Lexus IS F entered by Gazoo Racing (raced in 2007 and 2008) finished 1st and 2nd in the SP8 class[57] in the ADAC-Westfalenfahrt VLN 4h endurance race, beating out 3 other entrants, a Gallardo, a Corvette and a R8, whom all failed to complete the race. In winning its second VLN 4h event, the LF-A increased its fastest lap time, with one driver completing 8:41 laps both in practice and in the race;[58] by comparison, the fastest overall race laps were 8:27 by a Dodge Viper and a Porsche 997 Cup S, both of the new SP9 class, which is close to FIA-GT3. The LF-A was subsequently entered into the 24 Hours Nürburgring race for the manufacturer stated purpose of obtaining feedback for fine-tuning production versions[59] along with training of support technicians.[60] Gazoo registered two LF-As and a single IS F in the SP8 class (4000cc to 6200cc), as the LF-A racecars were powered by a 4.8-liter (4805cc) V10 engine with a 9000 rpm redline.[61][62]
At the 24 Hours Nürburgring endurance race held on May 23/24, the #15 LF-A[63] driven by Jochen Krumbach, Armin Hahne, Andre Lotterer, and Hiromu Naruse achieved sub-9min laps and a best time of 8:50.458, which was the fastest time in the SP8 class,[64] with a best lap speed of 172 km/h (107 mph);[64] the fastest times by the SP9 class race leaders were in the 8:40 range with a best lap speed of 176 km/h (109 mph).[64] About 90 minutes from race completion, the #15 LF-A experienced a separated driveshaft and a fire which poured white smoke from the vehicle's rear section.[65] The #14 LF-A completed the race and was ranked 4th in its class and 87th overall,[64][66] behind the 3rd ranked #16 IS F[67] During the early portions of the race the #14 LF-A recorded its peak position of 14th overall.[68][69] One of the drivers of the #14 car was Toyota's new CEO Akio Toyoda, who also met Aston Martin's President at the race before deciding to build the Aston Martin Cygnet together.[70]
[edit] Special models
In April 2005, Lexus presented a sculptural model of the original LF-A concept at that year's Milan Design Week exhibition in Milan, Italy. Part of the marque's introductory display of its L-finesse design theme, the full-size LF-A model was presented next to a production Lexus GS model, in a design space produced by painter Hiroshi Senju, designer Junya Ishigami, and architect Kazuyo Sejima.[71] The sculpted LF-A model followed the first introduction of the LF-A concept at the North American International Auto Show in January of that year. In contrast with the production GS sedan it shared the display space with, the LF-A model did not have interior access.
In April 2009, Lexus presented an acrylic glass sculpture LFA model, called 'Crystallised Wind', at that year's Milan Design Week exhibition at the Museo della Permanente art gallery in Milan. Commissioned in partnership with architect Sou Fujimoto, the full-sized LFA crystal sculpture had a transparent appearance, allowing viewers to see the engine, chassis, interior, and other internal components.[72] Although closely resembling the 2007 coupe concept, design elements on the LFA Crystallised Wind model differed from previous iterations of the coupe, with five-spoke wheels, different headlamp shapes, and other separate details. The vehicle was presented along with a collection of accessories, gadgets, and styling products all produced from the same acrylic materials used in the Crystallised Wind model.[73]
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