The Mugen Honda Legend Max Concept from 2005 was a one-off, high-performance version of the fourth-generation (KB1) Honda Legend/Acura RL created by Japanese tuner Mugen. It wasn’t a factory Honda model but a unique showcase of what the company could do combining racing tech with street car tuning. Under the hood it used a Mugen MF408S, a 4.0-liter naturally aspirated, 32-valve DOHC V8 developed by Mugen for motorsport use. In this car the engine was detuned slightly from its

The Mitsubishi Lancer Evolution Concept-X, shown in 2005 at the 39th Tokyo Motor Show, previewed the design and direction of the 10th and final Lancer Evolution. It introduced the sharper, more modern styling that later carried over to the production Evo X, along with the next generation of the Evo’s turbocharged, all-wheel-drive performance setup.

Shown at the 2005 SEMA show in Las Vegas, the Honda Ridgeline Street Sport Concept took the pickup in a street-focused direction, the opposite of Honda’s off-road All Terrain concept. It was built to explore a sport-truck look rather than off-road capability. The concept featured more aggressive front and rear bumpers, wider fenders, and dark Asphalt Shock Metallic paint. A prototype high-flow exhaust with side exits was added for sound and style, not extra power. The truck a

The Volkswagen Phaeton Individual Lounge Study, shown in 2005, was a one-off stretch version of the first-generation VW Phaeton luxury sedan. It was created as a design and engineering study to show how the Phaeton could be turned into a limousine-style vehicle, and it was unveiled at a Middle East motor show. Based on a lengthened Phaeton body, the Lounge Study stretched the wheelbase significantly to add more rear cabin space. It reportedly used the Phaeton’s powerful W12 e

The Mitsubishi Eclipse Ralliart concept, shown in 2005 at SEMA, was a one-off performance prototype built to show what a rally-inspired Eclipse could look like. It featured custom carbon-fiber bodywork, all-wheel drive, and a turbocharged 4G63 engine borrowed from the Lancer Evolution, producing around 400 hp.

The DC Design DC Star from 2005 was a custom two-door version of the first-generation Porsche Cayenne Turbo S created by Indian coachbuilder DC Design. Rather than being an official factory concept from Porsche, it was a coachbuilt showcase built around the Cayenne Turbo S platform and shown at events like the Dubai Auto Show. The DC Star took the normally four-door Cayenne SUV and reworked it as a two-door, more dramatic body style with bespoke exterior and interior touches

The Studiotorino RUF RK Spyder, shown in 2005, was a heavily modified version of the Porsche Boxster styled by Studiotorino and tuned by RUF. It used a supercharged 3.8-liter engine producing around 434 bhp, giving the small roadster serious supercar-level performance. Only 49 were built, making it very rare.

In the mid-2000s, Volvo offered the XC90 with a DOHC 32-valve V8 engine developed by Yamaha. In 2005, Volvo showed a supercharged version of the XC90 V8 at the Los Angeles Auto Show, hinting at a higher-performance model. That supercharged version was never sold to the public. The standard XC90 V8 remained on sale for a few years before the V8 option was discontinued in 2011.

The Mercury Meta One concept, shown in 2005, was a luxury crossover that previewed a diesel-hybrid powertrain. It was meant to signal a new direction for Mercury, blending upscale design with more efficient tech. The car never made it to production, and the Mercury brand was later discontinued before anything like it reached showrooms.

The Fiat Croma 8tto V, created in 2005 by Italdesign Giugiaro, was a one-off, high-end version of the Fiat Croma crossover. It was fitted with a Maserati-sourced V8 engine, turning the practical Croma into an over-the-top luxury performance concept that was never meant for production.

The Lotus Circuit Car Prototype, shown in 2005, was a track-only version of the Lotus Elise built for extreme performance. It weighed just 650 kg and used a supercharged VVTL-i engine. Thanks to its low weight and added power, it could sprint from 0–60 mph in about 3.5 seconds and reach 0–100 mph in around 9 seconds.

The Acura RL A-Spec concept, shown in 2005 at the Detroit Auto Show, previewed the A-Spec Performance Package that was later offered on the second-generation Acura RL (KB1). The KB1 RL was the North American version of the fourth-generation Honda Legend. It shared the same all-wheel-drive system, which Acura marketed as Super Handling All-Wheel Drive (SH-AWD).