The C5 Audi RS6 disguised supercar pace inside a restrained executive saloon and Avant. Developed with help from Cosworth Technology, it turned Audi’s aluminium-intensive 4.2-litre V8 into a twin-turbocharged 450PS flagship.
1. Cosworth Technology helped develop it
Audi owned Cosworth Technology at the time, and the Northampton operation was deeply involved in engineering and building the biturbo V8. This was an Audi programme, not a Cosworth-badged conversion, but the British link was real.
2. Its 4.2 V8 used two turbochargers
The 4,172cc engine produced 450PS and 560Nm, extraordinary output for a 2002 family car. Two turbochargers, twin intercoolers and revised internals distinguished it from the naturally aspirated S6.
3. Every regular RS6 used a five-speed Tiptronic
No manual was offered. Audi strengthened the torque-converter automatic, but its five ratios and the engine’s torque made the first RS6 feel very different from later dual-clutch performance cars.
4. Dynamic Ride Control used hydraulics, not air
DRC diagonally linked the dampers to resist pitch and roll without relying on electronically controlled air springs. It produced impressive body control, though ageing pipes and dampers became a well-known ownership issue.
Love cars you don’t see every day?
Get forgotten cars, surprising motoring stories and the most interesting finds from Unusual Cars by email.
Free to join. No spam. Unsubscribe whenever you like. See our Privacy Policy.
5. It was sold as both saloon and Avant
The Avant became the visual icon, but Audi also built a four-door saloon. North America received the saloon only, making body-style availability an important market difference.
6. The RS6 Plus raised output to 480PS
The final Plus version received revised engine management, additional cooling, a higher top-speed limit and dark exterior detailing. It was offered only as an Avant.
7. Audi limited the Plus to 999 cars
Each RS6 Plus carried a numbered plaque. Its small run and end-of-series specification make it the most collectable factory C5 derivative.
8. Its body was widened substantially
Unique front wings and rear quarter panels covered a broader track, while deeper bumpers and oval exhausts marked it out. The changes were muscular yet restrained beside many modern RS cars.
9. Performance rivalled contemporary supercars
Audi quoted roughly 4.7 seconds to 62mph for the standard car. The 250km/h limiter concealed even greater potential, while quattro traction made the pace accessible in poor weather.
10. It created the modern RS6 template
Every later RS6 followed its central idea: a discreet, practical large Audi with an engine and chassis capable of embarrassing dedicated sports cars. The C5 established that identity in one generation.
Love cars you don’t see every day?
Get forgotten cars, surprising motoring stories and the most interesting finds from Unusual Cars by email.
Free to join. No spam. Unsubscribe whenever you like. See our Privacy Policy.
Sources
- Unusual Cars RS6 C5 history
- Audi Tradition technical and production records.
