rear spoilers, and carbon ceramic brake discs. 2005–2006 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 , while its wheelbase measured The concept was nearly in height, with a width of . Some news outlets reported the concept name as referring to Lexus Future-Advance, a claim later dismissed by Chief Engineer Tanahashi. The first LF-A 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-pillars. Following enthusiastic public reaction for the LF-A concept on the auto show circuit, development continued with a greater emphasis on a possible production model. 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, however these reports were not officially confirmed. 2007–2008 Following the original LF-A concept, development time was lengthened by the switch from an aluminum frame to a carbonfibre tub, the result of engineering efforts aimed at improving the LF-A's power-to-weight ratio. The LF-A was reported to draw engineering resources from Toyota's Formula One team. 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 Great Britain director Steve Settle indicated plans for a V10 and hybrid version of the LF-A. The hybrid version, combining a petrol engine with electric motors, was to 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. In December 2007, Auto Express reported that the LF-A had set an unofficial 7:24 lap 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