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The CMST aero kit for the Audi A4 and A4L is a carbon-fibre lip package — a front lip and rear lip — offered in two fitments to cover both the 2008–2012 A4 and the 2012-onward A4L, with a matching 304 stainless cat-back exhaust. It is a bolt-on lip kit rather than a bumper swap or widebody: the carbon pieces mount to the factory bumpers, sharpening the lower body while keeping the A4's restrained executive look. Because the A4 sells in such large numbers, this kit exists to do one thing well — give an extremely common car a distinct, individual edge without major surgery.

• Vehicle: Audi A4 and A4L (long-wheelbase) saloon
• Fitment years: two versions — 2008–2012 A4 and 2012-onward A4L
• Material: Carbon fibre lips (vacuum-formed); 304 stainless exhaust
• Key pieces: Front lip, rear lip; optional cat-back exhaust
• Construction: Vacuum-bagged carbon for heat and wear resistance
• Install type: Add-on, reversible — bolts and bonds to factory bumpers

The A4 is the default executive saloon — well-built, sensible, and on every second street, which is precisely why owners look for a way to set theirs apart. The challenge is doing it in keeping with the car's understated character. A pair of well-shaped carbon lips is the answer. Here is what the kit adds and how the two fitments differ.

Two fitments for two generations

The most important thing to know about this kit is that it comes in two versions, because the A4 changed significantly across these years. The 2008–2012 A4 (B8) and the 2012-onward A4L (facelift and later) have different front and rear bumper shapes, so CMST tools the lips separately for each. Getting the right version is what guarantees the high fitment accuracy a lip kit depends on — a lip shaped for the wrong bumper will never sit flush. When ordering, the single most important detail is your exact year and whether your car is the A4 or the long-wheelbase A4L.

The carbon front lip

The front lip mounts to the lower edge of the factory front bumper and extends the chin forward, lowering the visual height of the nose and adding a splitter-style leading edge. CMST shapes the lip with a smooth curve that follows the contour of the original bumper closely, so it reads as a factory sports option rather than an add-on. Because it sits below the standard bumper, the parking sensors, number-plate mount and lower grille all stay as they were. The exposed carbon weave provides a dark contrast edge that works against any of the A4's common colours.

The carbon rear lip

The rear lip is the front lip's partner, capping the lower rear bumper to balance the lowered front. CMST highlights the construction here: the lips are made using a vacuum-bagging process, which compacts the carbon layers against the mould under vacuum to remove voids and excess resin. The result is a denser, more consistent part with good heat resistance and wear resistance — relevant at the rear, where exhaust heat and road grime are constant. Fitting both lips gives the A4 a lower, more cohesive stance front to back without touching the bumpers or arches.

The matching 304 stainless exhaust

For owners who want a sportier note to go with the sharper look, CMST offers a cat-back exhaust built from 304 stainless steel with a brushed finish. The 304 grade resists corrosion and the repeated heat-cycling that degrade cheaper mild-steel systems, so it stays clean and intact over years of use. It is a cat-back system designed to fit the factory mounting positions, replacing the rear section of the exhaust to free up flow and deepen the tone without altering the car's emissions hardware. The fit-and-finish — the weld quality and the way it sits in the standard hangers — is what separates a quality system from a generic one. For the construction details, see the CMST cat-back exhaust range.

Why a lip kit suits the A4

A lip kit is the right level of modification for a car like the A4. It keeps the executive restraint that is central to the car's appeal — no enlarged intakes, no flared arches — and simply lowers and sharpens the lower body. That makes it a sensible choice for owners who want their A4 to look individual without committing to a look that might date or that complicates resale. It is also reversible, since nothing is cut, which matters for leased and financed cars.

The carbon construction earns its place by holding its shape and edge at speed, resisting the sag of softer plastic lips, and providing a genuine exposed finish that needs no painting. To see the lips for your specific year, browse the CMST carbon fibre body kit for Audi, and the broader CMST body kit collection for Audi shows how the A4 pieces sit alongside the rest of the Audi range.

Fitment and finish

This is an add-on, reversible kit. Both lips mount to the factory bumpers using a combination of automotive-grade adhesive and fixings into existing points; nothing is cut, so the car can be returned to standard. The exhaust is a cat-back that fits the factory hanger positions.

A few practical points. The front lip sits lower than the standard bumper, so steep driveways and speed humps need a careful approach angle to protect the carbon edge. The lacquered carbon should be treated like paint — a UV-protective sealant once or twice a year keeps the weave clear under strong Australian sun. And, most importantly, order the version that matches your exact A4 or A4L year so the lips sit flush; professional fitment then ensures the lip lines are even on both sides.

The CMST Audi A4/A4L aero kit is a carbon-fibre front and rear lip package offered in two fitments — one for the 2008–2012 A4 and one for the 2012-onward A4L — with an optional 304 stainless cat-back exhaust. The lips are vacuum-formed for density and heat resistance, bolt to the factory bumpers, and keep the A4's executive look while lowering and sharpening the lower body.

Frequently asked questions

Does this kit fit my Audi A4?

It is offered in two versions to suit different generations: one for the 2008–2012 A4 (B8) and one for the 2012-onward A4L. The bumpers differ between these years, so the lips are tooled separately. Confirm your exact year and whether your car is the A4 or long-wheelbase A4L before ordering so the lips sit flush.

Is this a full body kit or a lip kit?

It is a lip kit — a carbon front lip and rear lip that bolt to the factory bumpers. It is not a bumper swap or a widebody, so it keeps the A4's standard panels and arches and simply lowers and sharpens the lower body. That suits the car's understated executive character.

What does "vacuum-formed carbon" mean here?

The lips are made using a vacuum-bagging process that compacts the carbon layers against the mould under vacuum, removing voids and excess resin. The result is a denser, more consistent part with good heat resistance and wear resistance — useful at the rear, where exhaust heat and road grime are constant.

Do the carbon lips need painting?

No. They are supplied in an exposed gloss-lacquered carbon weave and fitted as-is, so there is no colour-matching step. The carbon reads as a deliberate dark contrast edge against any of the A4's common paint colours.

Is the exhaust a full system?

It is a cat-back system — it replaces the exhaust from the catalytic converter back, built from 304 stainless steel with a brushed finish. It fits the factory hanger positions, frees up flow and deepens the tone, and leaves the car's emissions hardware unchanged. The 304 grade resists corrosion and heat-cycling better than mild steel.

Is the kit reversible?

Yes. Both lips attach to the factory bumpers with adhesive and existing fixings, and nothing is cut, so the A4 can be returned to standard. That makes the kit well suited to leased or financed cars.

Want to set your A4 apart without major surgery? Browse the CMST carbon fibre body kit for Audi at AME Motorsport, explore the matching CMST cat-back exhaust range, or talk to our team about which fitment suits your exact A4 or A4L and professional installation in Australia.