This one-off Audi TT is not what it seems

The late Ferdinand Piëch may have ruled with an iron fist, but he made sure things got done. During his tenure as CEO of the Volkswagen Group from 1993 to 2002, some of the company’s most ambitious engineering projects were approved, culminating in the development of the Bugatti Veyron. He left behind a complicated legacy, including costly vanity efforts such as the VW Phaeton, and visionary projects such as the XL1.

Even before Piëch took over the helm of the automotive giant, he played a crucial role in the development of several iconic cars. As head of development at Porsche and later at Audi, he was closely involved in projects such as the legendary 917 and Quattro racing cars. His drive to explore new ideas continued until the end of his leadership, and this TT lookalike serves as a prime example.

Despite its familiar silhouette, it is not really a tourist trophy. Photographed by rare_cars_deutschlandThe one-off took around eight months to complete and was the result of fusing an original TT body with a first-generation RS4 Avant. Essentially it was a B5 RS4 topped with an 8N generation TT body. Now you’re probably wondering why.

Around the turn of the century, Audi toyed with the idea of ​​a sports car that would be placed above the TT. The R8 did not yet exist, as the sister model to the Lamborghini Gallardo would not be shown until the 2003 Le Mans Quattro concept before entering production in 2006. To test the waters, Audi engineers combined the base of the RS4 Avant with the compact body of the TT. And by underbody we mean just about everything: axles, engine, rear differential, wheels, transmission and more.

To make the swap work, engineers shortened the chassis forward of the fuel tank by 170 millimeters to match the TT’s wheelbase and maintain proportions. Under the hood was the RS4’s 2.7-liter twin-turbo V-6 engine, making this prototype the only TT ever to use a true V-6, as the first two generations relied on VR-6s. Side note: The VW Group didn’t stop making VR-6 engines until late 2024.

Notably, the V-6 was mounted longitudinally, as opposed to the transverse layout of regular TTs. The drivetrain also switched from a Haldex differential to a more rear-biased Torsen system borrowed from the RS4. With 375 hp and 440 Nm of torque sent to all four wheels via a six-speed manual gearbox, the ‘TT Coupé RS4’ was a serious performer.

Unsurprisingly, performance was strong. After all, this was more RS4 than TT. It sprinted to 100 km/h in 4.9 seconds and reached a top speed of 280 km/h. The platform change did add some mass, bringing the curb weight to 3,417 pounds (1,550 kilograms), although the later VR-6-powered TT, launched in 2003, was only marginally lighter.

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Source: Rare Cars Deutschland

In a 2013 interview with the now defunct Fortitude On the website of former quattro GmbH (now Audi Sport) product chief Stephan Reil, he called the TT Coupé RS4 “incredibly fun to drive” and said it “outperformed a 911 at the time.” The car was heavily tested and has covered almost 20,000 kilometers.

As the Piëch era came to an end, the idea of ​​a production version proved too expensive to justify. The Volkswagen Group finally achieved its goal of building a supercar above the TT via the R8, paired with the Gallardo. Both the TT and the R8 have now been discontinued, but Audi plans to return to the sports car segment in 2027 with a production version of the Concept C. This time completely electric.