Audi RS4 Cabriolet

Convertible 2006–2008 420 hp Petrol V8

The Audi RS4 Cabriolet is the only open-top RS4 ever produced — a unique combination of 420 hp naturally aspirated V8, quattro permanent AWD, and cabriolet body that Audi built for just two years, creating one of the rarest and most desirable RS models ever made.

420

Horsepower

5.1s

0–100 km/h

250km/h

Top Speed (limited)

430Nm

Peak Torque

Overview

The Audi RS4 Cabriolet (B7) was produced from 2006 to 2008 as part of the B7-generation RS4 family, which represented the peak of Audi's naturally aspirated performance philosophy. Using the same 4.2-litre FSI V8 engine as the RS4 Saloon and Avant — producing 420 hp at 7,800 rpm and 430 Nm at 5,500 rpm — the Cabriolet variant added open-air motoring to the RS4's performance credentials. The engine's high-revving character, with its peak power appearing at 7,800 rpm and a 8,250 rpm redline, gave the RS4 Cabriolet an intensity of performance experience that turbocharged competitors could not replicate. Reaching 100 km/h from rest in 5.1 seconds with the roof down — or matching the saloon's 4.9 seconds with the roof up and aerodynamic drag reduced — the Cabriolet sacrificed only minimal performance versus its closed siblings.

The quattro AWD system in the RS4 Cabriolet used a Torsen T-3 centre differential with a 40:60 front-to-rear torque bias, distributing power between axles continuously without driver intervention. This system gave the open-top car exceptional traction even in poor conditions — the quattro AWD largely compensating for the cabriolet body's reduced structural rigidity through better traction management. The fabric soft-top — a 3-layer acoustic fabric hood with heated glass rear window — could be lowered in 30 seconds and operated at speeds up to 50 km/h while moving. The B7 RS4 Cabriolet was produced in limited numbers — approximately 3,500 units over its two-year production run — making it significantly rarer than either the RS4 Saloon or Avant of the same generation.

In the Azerbaijani market, the RS4 Cabriolet occupies an exceptional position as one of the rarest RS models available. The combination of naturally aspirated V8 sound, open-air motoring, and quattro traction creates an ownership experience that cannot be replicated by any current Audi product. As a collector-grade vehicle, values for well-maintained low-mileage examples have stabilised and in some markets begun to appreciate, reflecting growing recognition of the B7 RS4's engineering significance. Buyers should approach purchase with a comprehensive understanding of the V8's maintenance requirements and the additional complexity of the cabriolet roof mechanism — both of which demand specialist attention.

RS4 Cabriolet in Pictures

Visual references for exterior styling, cabin design, and key details. Images fall back gracefully on load error.

The Audi RS4 Cabriolet (B7) — the only open-top RS4 ever built, combining 420 hp V8 performance with open-air motoring

With the roof down, the RS4 Cabriolet's quad exhaust tips and widened rear arches announce its performance credentials

The RS4 Cabriolet's fabric soft-top opens in 30 seconds and can be lowered at speeds up to 50 km/h while moving

The B7 RS4 interior features full-bucket RS sport seats, carbon-fibre inlays, and a flat-bottomed RS steering wheel as standard

Key Specifications

Body: 2-door cabriolet with 3-layer acoustic fabric soft-top and heated glass rear window
Engine: 4.2 FSI V8 naturally aspirated — 420 hp at 7,800 rpm / 430 Nm at 5,500 rpm
Drive: quattro permanent AWD — Torsen T-3 centre differential, 40:60 front-rear torque split
Transmission: 6-speed manual (standard) or 6-speed torque-converter automatic
0–100 km/h: 5.1 s (auto) / 4.9 s (manual) | Top speed: 250 km/h (electronically limited)
Redline: 8,250 rpm — one of the highest-revving production AWD cars ever built
Production volume: approx. 3,500 units (2006–2008) — B7 generation exclusive
Brakes: vented front 365 mm with 6-piston callipers; ceramic composite optional (CCMB)

Variant Comparison

Variant	Engine	Power	Drive	Best For
RS4 Cabriolet (420 hp)	4.2 FSI V8 naturally aspirated	420 hp	quattro AWD	RS enthusiasts and collectors who want the purest, most exclusive expression of the B7 RS4 family — the cabriolet's rarity, the V8's character, and quattro AWD combine in a way never repeated
A4 Cabriolet 3.0 TDI (204 hp)	3.0 TDI V6 turbodiesel	204 hp	Front-wheel drive	Buyers who want A4 Cabriolet practicality with diesel economy — the TDI variant offers everyday usability and lower running costs for those who prioritise open-air motoring over performance
S4 Cabriolet 4.2 V8 (344 hp)	4.2 FSI V8 naturally aspirated	344 hp	quattro AWD	Buyers who want V8 performance in the A4 Cabriolet at lower cost than the RS4 — the S4 Cabriolet uses the same V8 in lower state of tune but at significantly more accessible prices

Competitor Snapshot

Model	Strength	Compromise
BMW M3 Convertible (E93)	The BMW M3 Convertible (E93) offered a lighter, more driver-focused cabriolet with sharper handling dynamics, an equally charismatic naturally aspirated V8 engine, and the advantage of rear-wheel drive which many enthusiasts prefer for track use	The BMW M3 Convertible had no AWD — the Audi RS4 Cabriolet's quattro system provides significantly better traction in rain and snow, making it more usable year-round in countries with variable weather; the BMW also had a heavier retractable hardtop versus the Audi's lighter fabric roof
Mercedes-AMG CLK 63 Cabriolet	The Mercedes-AMG CLK 63 Cabriolet offered a larger 6.3L naturally aspirated V8 producing 481 hp, wider torque curve, and more relaxed cruising ability with the Mercedes luxury interior appointments that some buyers preferred over the sportier Audi environment	The CLK 63 was rear-wheel drive only — significantly less capable in poor conditions than the RS4 Cabriolet's quattro; it was also available in smaller numbers and has proven more expensive to maintain due to the AMG engine's bespoke components
Porsche 911 Carrera Cabriolet (997)	The Porsche 911 Carrera Cabriolet (997) offered superior driving dynamics, better resale value retention, greater engineering purity, and the Porsche brand prestige that in many markets outweighs all competitors in the performance cabriolet segment	The 911 Cabriolet was significantly more expensive than the RS4 Cabriolet, offered no AWD (Carrera) or was even more expensive with AWD (Carrera 4), and had a much smaller interior with no practical rear seats — the RS4 Cabriolet was significantly more usable as a four-seat performance convertible

Cost-of-Ownership Estimator (Azerbaijan)

Annual distance (km)Fuel consumption (L/100km)Fuel price ($/L)Annual service budget ($)Annual insurance ($)Annual tires ($)

Annual fuel use: 1740 litres
Annual fuel cost: $1131
Total yearly estimate: $7331
Monthly average: $611

The 4.2 FSI V8 requires strict 5,000 km oil change intervals with 5W-40 fully synthetic — the engine uses an aluminium block with tight tolerances; extended intervals cause carbon buildup on the inlet valves that is expensive to clean on a direct-injection V8.
The cabriolet soft-top mechanism requires annual lubrication of all pivot points and guide rails — neglect causes premature wear of the electric motor and hydraulic cylinders that operate the hood, with replacement costs exceeding €1,500 for the complete mechanism.
The quattro AWD system's Torsen differential requires correct transmission fluid specification — use only Audi-approved gear oil in the transfer case; incorrect fluid causes temperature-related differential wear that is very expensive to repair.

Maintenance & Service in Azerbaijan

Engine oil service every 5,000 km with 5W-40 Audi-approved fully synthetic — the 4.2 FSI V8 with its tight bearing clearances and direct injection requires frequent clean oil; carbon deposits on inlet valves are a known issue that worsens significantly with extended oil change intervals.
Timing chain service inspection at 80,000 km — the B7 RS4's 4.2 FSI uses a timing chain rather than belt; chains are long-lived but the tensioners on the V8 are known to weaken on high-mileage examples, producing a rattle on cold start that indicates imminent replacement.
Cabriolet roof mechanism lubrication annually — apply approved roof mechanism lubricant to all guide rails, pivot points, and the seal channels; dry pivot points cause the electric actuators to work harder, accelerating wear that leads to expensive mechanism failure.
Brake fluid replacement every 2 years — the RS4 Cabriolet's large vented front discs (365 mm) generate significant brake heat during spirited driving; degraded brake fluid with absorbed moisture causes pedal fade under repeated hard braking.
Roof seal inspection and conditioning every 6 months — apply rubber conditioner to all door and windscreen seals; the B7 Cabriolet's multiple seals are prone to hardening in temperature extremes, causing water ingress that leads to interior water damage.

Used RS4 Cabriolet Buying Checklist

Test the cabriolet roof through a complete open-close cycle — the mechanism should complete the sequence smoothly without hesitation, grinding, or motor strain; any irregular movement indicates a failing hydraulic or electric actuator.
Inspect for water ingress in the interior boot area and carpet — wet carpets or staining under the rear seat indicate roof seal failure or drainage channel blockage that has already caused damage to the interior.
Listen for the V8 timing chain rattle on cold start — let the engine idle from cold and listen for any metallic rattle in the first 10–15 seconds of running; this indicates worn chain tensioners that require immediate replacement.
Check for carbon buildup symptoms — rough idle, hesitation at part-throttle, or uneven cylinder contribution (visible as slight vibration at idle) suggests inlet valve carbon deposits that require walnut blasting to clean.
Verify quattro AWD function by accelerating firmly on a loose or wet surface — all four wheels should pull evenly; any wheelspin from a single corner suggests a worn rear differential or coupling issue.
Check the V8's throttle response across the full rev range — the 4.2 FSI should pull strongly from 3,000 rpm to its 8,250 rpm redline without flat spots; any hesitation or power loss under load suggests injector or ignition service required.

RS4 Cabriolet FAQ — Azerbaijan Buyers

Q: Why was the RS4 Cabriolet only produced in the B7 generation and not before or after?

The B7 RS4 Cabriolet was enabled by the specific combination of the naturally aspirated 4.2 FSI V8 and the A4 Cabriolet body platform that happened to coincide in the same generation. Previous RS4 generations (B5, B6) either did not have cabriolet body variants in the A4 lineup at the appropriate time or were not planned as open-top models. After the B7 generation, the RS4 switched to turbocharged V6 engines (B8, B9) and the A4 Cabriolet body was discontinued — replaced by the A5 Cabriolet. The B7 RS4 Cabriolet therefore represents a unique moment in Audi's history when all necessary elements — the V8 engine, quattro AWD, and cabriolet body — existed simultaneously.

Q: How does the naturally aspirated V8 compare to the turbocharged engines in newer RS models?

The 4.2 FSI V8 in the B7 RS4 delivers power in a fundamentally different way from turbocharged engines. Peak power occurs at 7,800 rpm — meaning the driver must rev the engine hard to access its full potential, which creates an involving, rewarding driving experience. Modern turbocharged RS engines (like the 2.9 biturbo V6 in the B9 RS4) produce peak torque from very low rpm — offering faster acceleration from everyday speeds but a less emotional, less demanding drive. The V8 also produces a naturally aspirated exhaust note that many enthusiasts consider superior to the sound of turbocharged engines. In practical terms, the turbo engines are faster in everyday conditions; the V8 rewards the driver who explores its capabilities.

Q: What are the main mechanical concerns with the B7 RS4 Cabriolet?

The primary mechanical concerns are: (1) Carbon buildup on inlet valves — inherent to direct injection engines of this era; symptoms include rough idle and hesitation; treatment is walnut blasting which costs €800–1,200. (2) Timing chain tensioner wear — on high-mileage examples, a cold-start rattle indicates tensioner fatigue; replacement is a major job but must be done promptly. (3) The throttle actuator system can develop failures causing hesitation or stuck throttle — a known B7 V8 issue. (4) The cabriolet roof mechanism hydraulic seals degrade with age; replacement is expensive but the mechanisms are repairable by specialists.

Q: Is the RS4 Cabriolet practical for everyday use?

As a daily driver, the RS4 Cabriolet has reasonable practicality for a convertible. The quattro AWD system gives it traction in all conditions that typical open-top sports cars lack. The 400-litre boot (roof up) is adequate for everyday use though significantly reduced compared to the saloon. Fuel consumption is the primary practical concern — expect 15–18 litres/100 km in mixed use given the large V8, which makes running costs substantial. The 2006–2008 era electronics are generally reliable but some comfort control modules and infotainment components show age-related failures. As a car used 3–4 times per week rather than every day, these considerations are manageable for buyers who value the unique experience it offers.

Q: What is the expected value trajectory for the RS4 B7 Cabriolet?

The B7 RS4 Cabriolet is increasingly recognised as a collector-significant vehicle. Values for genuinely low-mileage, single-owner, well-documented examples have been rising in European markets since approximately 2020, following the broader appreciation of naturally aspirated performance cars from the early 2000s. The rarity factor — approximately 3,500 units produced — combined with the uniqueness of the V8 cabriolet AWD combination makes the car special in a way that most RS models are not. Buyers looking at investment potential should focus on documented service history, original condition (unmodified), and low mileage; these examples are appreciating while high-mileage or modified cars remain static.

Should You Buy the Audi RS4 Cabriolet?

The RS4 Cabriolet is the only open-top RS4 ever built — a unique combination that Audi will never repeat.

For the enthusiast who wants something genuinely rare and historically significant, the B7 RS4 Cabriolet represents an opportunity that will not persist. The naturally aspirated 4.2 V8 with its 8,250 rpm redline creates an experience that no current Audi — with its turbocharged powertrains and electronic management — can replicate. The quattro AWD system means it can be used confidently in rain or cold, which typical cabriolets cannot. Yes, running costs are significant: fuel consumption is high, maintenance must be meticulous, and specialist knowledge is required. But for the right buyer — someone who wants a performance car with real rarity, real mechanical soul, and an ownership experience unlike any contemporary alternative — the RS4 Cabriolet is extraordinary.