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The CMST widebody kit for the Mercedes-Benz A180 is a multi-piece aero package that mixes FRP (fibreglass-reinforced plastic) bumpers and fenders with dry carbon-fibre lips, side-skirt blades, a vented bonnet and a rear wing. It is designed around the W176 A-Class hatch, with FRP front fenders CNC-matched to the factory body for a claimed fitment accuracy near 90%, and it pairs with a SUS304 stainless steel cat-back exhaust. Every panel bolts or bonds to the original mounting points, so the A180 keeps its road manners while gaining genuine widebody presence.

• Vehicle: Mercedes-Benz A180 / A-Class (W176 hatch)
• Fitment: W176 A-Class, 2013 onward (pre-facelift body)
• Material options: FRP (bumpers, fenders, wheel arches, side skirts) and dry carbon fibre (front lip, rear lip, skirt blades, intake vents, bonnet, rear wing)
• Key pieces: Front bumper, front lip (street and track versions), rear bumper, dual-exit rear lip, side skirts + carbon under-blades, front fenders, rear wheel arches, carbon bonnet, carbon rear wing
• Finish: Primer-ready FRP for paint-matching; exposed twill or satin clear-coat carbon

What the CMST A180 widebody kit actually includes

This is a full-body conversion rather than a styling add-on. The package widens the car at the front fenders and rear arches, then ties the new bodywork together with lips and skirts so the proportions stay coherent. Because the A-Class is the smallest model in the Mercedes range, a widebody treatment has an outsized effect: a modest arch flare visually drops the car and broadens the stance far more than it would on a larger saloon.

CMST splits the kit by material on purpose. Large, impact-prone panels — the front and rear bumpers, fenders and arches — are moulded in FRP, which is easier to repair, simpler to paint to factory colour, and more forgiving of kerb contact. The aerodynamic accents that benefit from a premium finish — the front and rear lips, skirt under-blades, intake surrounds, bonnet and wing — are offered in dry carbon fibre, where the woven surface is part of the look. If you are comparing options across the range, our CMST body kit for Mercedes-Benz collection lists the panels available for each chassis.

Front: bumper, lip and intake vents

The front bumper is an FRP replacement that integrates a deeper splitter area and enlarged corner intakes feeding the brakes and cooling. CMST offers the front lip in two carbon variants: a street version with a shallower leading edge for daily clearance, and a more aggressive track version that protrudes further to add high-speed downforce. Carbon intake surrounds finish the corner ducts. The result is a wider, lower face that still clears typical driveways when the street lip is fitted. Buyers who only want to refresh the nose can browse the CMST front lip for Mercedes-Benz range.

Sides: fenders, skirts and arches

The FRP front fenders are the structural heart of the widebody. CMST states they are built from precise factory scan data for around 90% out-of-the-box fitment, which reduces the trimming and packing usually needed on cheaper flares. FRP rear wheel arches add width that CMST describes as moderate rather than exaggerated, keeping the tyre covered for road legality. FRP side skirts run the length of the sill, and a separate carbon under-blade sharpens the lower edge and visually connects the front splitter to the rear. You can view arch and skirt options in the CMST fenders for Mercedes-Benz and CMST side skirts for Mercedes-Benz collections.

Rear: bumper, dual-exit lip and diffuser

At the back, an FRP rear bumper houses a carbon rear lip cut for a dual-side, twin-tip exhaust layout. The lower section incorporates a diffuser-style strake panel that tidies airflow leaving the underbody. Paired with the wider arches, the rear gains the planted, square-shouldered look that the standard A-Class lacks.

Bonnet and rear wing

The carbon bonnet is moulded with recessed channels down each side, giving the flat factory panel sculpted definition and shedding weight over the steel original. CMST notes a vacuum-formed carbon process for the panel; on a turbocharged A180 the added surface relief and any functional venting help release under-bonnet heat. The carbon rear wing carries a clearly visible weave and a raised aerofoil profile that adds rear-axle stability at speed while finishing the silhouette. Matching wings and bonnets are grouped under the CMST wing for Mercedes-Benz and CMST hood for Mercedes-Benz collections.

Dry carbon vs FRP: which material for which panel

Choosing materials is the most important decision on this kit, so it is worth understanding the trade-offs rather than defaulting to "all carbon".

For an A180 used mainly on the road, the factory split CMST supplies is sensible: paint the FRP arches and bumpers to your body colour for a seamless OEM-plus look, and leave the carbon lips, bonnet and wing exposed as contrast accents. Owners chasing maximum weight saving can specify carbon for the larger panels too, at higher cost. Compare full carbon and FRP variants in the All Carbon Fibre Body Kit collection.

The matching SUS304 stainless cat-back exhaust

CMST builds the A180 mid-and-rear exhaust section from SUS304 stainless steel with a brushed finish. SUS304 is the international-standard grade for performance exhausts because it resists corrosion and tolerates repeated heat cycling, and it is lighter than the heavier mild-steel factory system. Shortening and smoothing the exhaust path — straightening the sharper factory bends — reduces back-pressure, which can improve exhaust flow and throttle response. The dual-exit tips line up with the cut-outs in the carbon rear lip. We do not quote specific power figures here because gains depend on the rest of the car, but a freer-flowing cat-back is a sound foundation for a turbocharged four-cylinder.

Fitment and finish in Australia

Because the kit is a bolt-on/bond-on conversion using factory mounting locations, it suits professional installation by a workshop experienced with European hatches. Plan for paint preparation on the FRP panels, test-fitting of the wider fenders and arches before final paint, and verification that the chosen tyre and wheel package sits correctly under the new arches. In Australia, fit the street front lip if your driveways and speed humps are steep; the track lip is better reserved for smoother roads and events. Always confirm guard clearance and tyre coverage for roadworthy compliance in your state. To plan a full build, start with the broader All Body Kit catalogue or the dedicated CMST brand page.

Frequently asked questions

Does the CMST A180 widebody kit fit all A-Class models?

It is designed for the W176 A-Class hatch (the generation that includes the A180, A200 and A250). It is not designed for the later W177 A-Class or the A-Class saloon. Confirm your exact model year and body style before ordering, as the pre-facelift and facelift bumpers differ.

Is the kit carbon fibre or fibreglass?

Both. CMST supplies the bumpers, front fenders, rear wheel arches and side skirts in FRP (fibreglass-reinforced plastic), and the front lip, rear lip, skirt under-blades, intake surrounds, bonnet and rear wing in dry carbon fibre. This keeps repairable panels affordable while putting the premium carbon finish on the visible aero pieces.

Do I need to paint the panels?

The FRP panels are supplied primer-ready and are intended to be painted to your car's colour for a factory-matched look. The carbon pieces come with a clear-coated woven finish and are usually left exposed, though they can be painted if you prefer a colour-matched body.

Will the widebody arches be roadworthy in Australia?

CMST designs the arches to cover the tyre, which is the key requirement, but legality depends on your final wheel and tyre fitment and your state's guard-clearance and tyre-coverage rules. Have the car inspected after installation and choose an offset that keeps the tyre within the new arch line.

Does the carbon bonnet help engine cooling?

The bonnet is lighter than the steel original and is moulded with sculpted channels; any functional venting on the panel assists in releasing heat from the turbocharged engine bay. Its primary benefits are weight reduction over the nose and appearance.

Can I buy individual pieces instead of the full kit?

Yes. The front lip, rear lip, bonnet, wing, fenders and skirts are available individually, so you can stage the build — for example starting with the front lip and skirts, then adding the wider fenders and arches later. Browse the per-piece Mercedes-Benz collections linked above.

Ready to specify your A180 conversion? Explore the full CMST body kit for Mercedes-Benz range at AME Motorsport, or contact our team to confirm fitment, material choices and paint options for your build.