| The Weapon |
10-21-2009 02:07 PM |
Here's some more info on the specs:
Quote:
Road & Track Magazine - Technical Analysis: 2011 Lexus LFA (12/2009)
When Chief Engineer Haruhiko Tanahashi was charged to lead the Lexus LFA sports-car program in 2000, he had a rare opportunity — every engineer's dream — to design a supercar from a clean sheet of paper. However, at the time, Toyota's highest-performance car to date was the Supra, and it never played in the same supercar category as Ferrari, Lamborghini or Porsche. Tanahashi had to proceed without having the luxury of a previous Toyota supercar. And so it took 10 years — learning and improving continuously — before the LFA would finally be ready to be unveiled.
Slideshow >>
As with any super sports car, the heart and soul of the LFA is its engine. Work began on the LFA's powerplant within a year of Tanahashi's arrival. The all-new 4.8-liter aluminum V-10 has exterior dimensions comparable to a typical Toyota V-8's, but weighs about the same as a V-6. The front mid-mounted power unit serves up 560 bhp (DIN) at a dizzying 8700 rpm. Peak torque of 354 lb.-ft. arrives at 6800 rpm. Employing intelligent variable valve timing (VVT-i) on both the intake and exhaust, the engine produces 90 percent of its maximum torque at only 3700 rpm. A 72-degree vee angle helps minimize first and second order vibrations, a natural concern in a V-10 with a lofty 9000-rpm redline.
To achieve quick and smooth engine response for its V-10, Toyota worked with longtime partner Yamaha — well known for its high-speed valvetrain expertise. Individual throttle bodies for each cylinder, forged aluminum pistons and carbon-coated rocker arms (with integrated oil jets), plus titanium connecting rods and valves, contribute to the engine's ability to rev from idle to 9000 rpm in a mere 0.6 sec. In fact, the powerplant spools up so quickly that only a digitally simulated analog tachometer can keep up. Making sure the engine is well lubricated while operating at extreme loads is a dry sump system capable of sustaining cornering forces of more than 2g. Although incredibly potent, the LFA's V-10 meets the Euro V emissions regulations thanks in part to early light-off of the catalytic converters during cold starts.
For Tanahashi, absolute sports-car driving pleasure is as much about having a proper engine note as it is having a responsive engine. Here again, Toyota worked with Yamaha to fine-tune the acoustics of the V-10. Through a two-stage air intake integrated into one resonant chamber, and also via a split equal-length exhaust manifold leading to a multi-stage silencer, the LFA's powerplant belts out a Formula 1-like wail that will grab anyone's attention. The varying sound from the resonant air chamber (from 300 Hz at 4000 rpm to 600 Hz at the 9000-rpm redline) is piped into the cockpit below and above the dashboard so the occupants can also enjoy the race-tuned engine shriek.
Slideshow >>
Mated to the LFA V-10 is a transaxle driving the rear wheels, featuring a 6-speed, single-clutch paddle-shift transmission. The clutch actuation is hydraulic, the system cooled by a dedicated oil cooler. To ensure smooth operation, triple synchros are installed on the first four gears, and double synchros are in place for the remaining two. There are four gearbox modes to choose from: Auto, Sport, Normal and Wet. In Sport, where manual shifting is required, there are seven shift settings that enable the transmission to swap gears in as little as 0.2 sec., or a more lengthy 1.0 sec. for smoother operation during cruising. Integrated within the transaxle is a torque-sensing limited-slip differential that helps you turn more of that 560 bhp into forward motion when exiting corners.
The LFA chassis consists of three main pieces: a Carbon Fiber Reinforced Plastic (CFRP) center tub, and aluminum alloy subframes extending forward and back. Toyota relied on its own extensive textile weaving heritage and expertise to help construct the carbon-fiber tub. Labor-intensive resin-impregnated carbon-fiber sheets are hand laid to form the exceptionally stiff and strong cabin structure. Resin Transfer Molding (RTM), where preformed carbon fiber is impregnated with resin, is used for the floor, transmission tun nel and hood. Sheet Molding Compound (C-SMC), where short-fiber carbon-fiber material is hot-pressed into a die, is used for the C-pillars and the rear floor. In total, CFRP accounts for 65 percent of the weight of the LFA's body-in-white, with aluminum alloys representing the remaining 35 percent. With the CFRP, Toyota estimates it's about 220 lb. lighter than an all-aluminum structure.
Keeping the LFA firmly planted on the asphalt is its suspension, which features double A-arms in front, a multilink rear, and non-adjustable springs and shocks. Carbon-ceramic rotors, 15.4 in. up front and 14.2 in. at the rear, are on duty to slow the car with confidence and minimal fade. Bridgestone has provided specially designed 20-in. asymmetric-tread tires, with 265/35s leading and 305/30s following.Aero grip is enhanced by the LFA's flat underbody and carbon-fiber rear diffuser, plus a rear wing that will deploy at speeds greater than 50 mph. The overall drag coefficient is 0.31. Additionally, a varying-degree (from Normal to Sport to fully defeatable) stability control system is there to provide that extra layer of safety when needed.
Even though Tanahashi and his team have taken 10 years to develop the LFA, these engineering perfectionists probably wish they had more time with the car. All we can say is this: We're glad Toyota's first supercar has finally arrived.
|
|
