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The CMST widebody Mustang programme is a dry-carbon and FRP wide-arch aero kit for the 2015-2017 (S550) Ford Mustang. It fits both the 2.3 EcoBoost and the 5.0 V8 GT, and it covers the car from nose to tail: a carbon front lip with canards, an FRP front bumper, a tri-peak vented carbon bonnet, four flared widebody arches, vented front fenders, carbon side skirts, a carbon rear lip and diffuser, and a carbon GT rear wing. The kit has appeared on S550 builds worldwide and was displayed as a finished widebody Mustang at the 2016 Vancouver International Auto Show.

One thing this kit is known for is the sheer range of colours it turns up in. The same arches and panels have been built in silver, jade green, dark grey, red and orange, and that variety is by design rather than chance: the FRP arches and fenders ship primed for colour-matched paint, while the carbon show panels keep their woven finish under clearcoat. The result is a widebody that reads as factory-integrated whatever paint code sits over it.

• Vehicle: Ford Mustang, S550 generation (2015-2017)
• Fitment: 2.3 EcoBoost and 5.0 V8 GT coupe; widens the track for wider wheels and tyres
• Material options: Dry carbon fibre (2x2 twill, clearcoated) for the show panels; FRP (fibreglass-reinforced plastic) for the arches, fenders and front bumper
• Key pieces: Front lip + canards, FRP front bumper, tri-peak vented carbon bonnet, four widebody arches, vented front fenders, carbon side skirts, carbon rear lip + diffuser, carbon GT wing
• Finish: Paint-to-colour FRP arches and fenders (shipped primed); exposed 2x2 twill carbon weave under gloss clear on the carbon pieces

What the CMST widebody Mustang kit is

This is a full wide-arch aero conversion built around one car: the S550 Mustang. Rather than a single bumper or a bolt-on lip, CMST designed the pieces as a set that works together around the Mustang's body lines, widening the track and reshaping the car's stance front to rear. The carbon parts carry a real 2x2 twill weave under clearcoat; the larger structural arch and fender pieces are moulded in FRP, which is easier to repair and paint over a big flared surface. You can fit the whole package or build toward it piece by piece from the Ford Mustang body kit range.

Because the kit mixes two materials, it is worth being clear on which part is which. The aero details that benefit from light weight and a visible weave — the front lip, canards, bonnet, side skirts, rear lip, diffuser and wing — are carbon. The four arches, the vented front fenders and the front bumper are FRP, because those are the pieces most likely to need colour-matching to your Mustang's paint and the most practical to refinish. The full breakdown lives in the CMST body kit for Ford collection.

The wide-arch design language

The defining idea of this kit is track width. The front arches push the bodywork out by roughly 5cm and the rears by roughly 6cm per the design, which does two things at once. It clears noticeably wider wheels and tyres, and it gives the Mustang a planted, square-shouldered stance that the standard car does not have. The flares are not tacked-on lips; they are full arch sections that blend into vented front fenders, so the widened body reads as one continuous line rather than a bolt-on add-on.

That extra width is the reason the kit pairs naturally with 20-inch forged wheels. A wider track and a deeper wheel-and-tyre package fill the new arches properly, and the vented fenders relieve pressure from the front wheel wells. The whole shape is built to look deliberate from any angle, which is also why it photographs so consistently across very different colours. You can see the wheel options that suit the conversion in the CMST forged wheels for Ford range.

Piece by piece

Front lip and canards

The carbon front lip runs along the lower edge of the FRP front bumper and works as much aerodynamically as visually. A front lip helps manage airflow under the nose and reduces front-axle lift at speed, which steadies the Mustang's front end on the open road. The canards sit on the front corners, adding bite to the look while helping direct air around the wheel openings. Together with the reshaped FRP bumper, they give the S550 a more aggressive face without touching the factory lights or grille.

Vented carbon bonnet

The bonnet is a tri-peak vented carbon design that replaces the factory steel panel. Its raised central peaks and vents are functional in intent: they help extract heat from the engine bay, which matters on the 5.0 V8 GT in particular. Being carbon rather than steel, it is lighter while keeping the stiffness a bonnet needs, and it carries the same twill weave as the rest of the carbon pieces. We won't quote a kilogram saving, because the real figure depends on the exact panel and hardware, but removing mass from the highest, most forward point of the car is a genuine benefit.

Widebody arches and fenders

This is the heart of the kit. Four flared FRP arches replace the standard wheel-arch line — front and rear, both sides — and the front pair integrates with vented FRP fenders. The arches are what create the wider track, pushing the body out around 5cm at the front and 6cm at the rear. Because they are FRP and ship primed, a workshop can paint them to your exact colour so the flares disappear into the bodywork rather than standing out as grey add-ons. The matching widebody pieces are in the CMST widebody fenders for Ford collection.

Side skirts

The carbon side skirts run along the sills between the front and rear arches. Visually they lower the car's profile and tie the widened front to the widened rear, so the conversion reads as one piece down the flank. Aerodynamically they smooth airflow along the sides and reduce the air spilling under the car. In carbon, they also bring the weave finish down to the lower body, which keeps the detailing consistent with the lip, diffuser and wing.

Rear lip and diffuser

At the back, the carbon rear lip and diffuser add depth to the lower bumper and tidy airflow leaving the car. CMST offers the rear in two layouts to match the exhaust: a dual single-exit version and a dual-dual-exit version, so the diffuser cut-outs line up with the pipe arrangement on your Mustang. The diffuser's strakes give the tail a layered, three-dimensional look while the carbon weave keeps it consistent with the front of the car.

GT rear wing

The carbon GT rear wing is the kit's most overt aero piece. Where a small ducktail only styles the boot, a raised GT wing adds genuine rear downforce at speed, which helps high-speed stability and balances the front lift reduction from the lip and canards. It finishes the widebody silhouette with the same twill carbon as the rest of the package. The full CMST carbon fibre body kit range shows how the wing sits against the other carbon pieces.

Finished in any colour

This is why one kit can look right in silver, green, grey, red and orange. The FRP arches, fenders and front bumper ship in primer, ready for a body shop to spray them in your Mustang's exact paint code. Once colour-matched, the flares integrate into the bodywork instead of reading as a separate widebody bolt-on. The carbon pieces are the deliberate contrast: the lip, bonnet, skirts, diffuser and wing keep their woven 2x2 twill under clearcoat, so every build carries the same carbon accents regardless of the body colour. A jade-green car and a silver car end up with the same carbon signature and a paint-matched widebody — only the base colour changes.

That split also makes the kit forgiving to live with. Painted FRP is straightforward for any panel shop to touch up after a kerb scuff, while the carbon parts hold their finish under clear. It is a practical way to get a show-grade widebody that still suits a car you actually drive.

Dry carbon vs FRP

The kit deliberately uses two different materials, and it helps to understand why. Dry carbon is the premium structural choice for the show panels; FRP is the sensible choice for the large painted flares; and both sit above the factory's PP plastic in rigidity and finish.

Material	How it is made	Strengths	Trade-offs
Dry carbon fibre	Pre-impregnated ("prepreg") carbon sheets laid into a mould and cured under heat and pressure in an autoclave	Very light and stiff; shows a true 2x2 twill weave under clear; holds its shape and finish like a supercar part	More expensive; the exposed weave benefits from UV care over years of sun
FRP (fibreglass-reinforced plastic)	Glass-fibre matting laid up with resin in a mould, then primed for paint	Strong and rigid over large arch surfaces; easy to paint to any colour and to repair after a knock	Heavier than carbon; has no weave to show, so it is meant to be painted, not left bare
Factory PP plastic	Injection-moulded polypropylene (the standard bumpers and trims)	Cheap, flexible and light for everyday use	Relatively soft for its weight; no weave; not designed for a widened, aggressive aero shape

Bringing the look to an Australian Mustang

On an S550 here, the conversion is workshop fitment rather than a driveway job. The widebody arches and vented fenders need to be mounted and aligned to the body, the FRP pieces painted to your colour code by a panel shop, and the carbon aero test-fitted so gaps sit evenly. Because the kit widens the track, wheel and tyre choice matters: a 20-inch forged setup with the right offset fills the new arches and keeps clearance correct through full suspension travel and steering lock. A fitter experienced with widebody work will check guard clearance and roll or trim where needed so the tyres never catch.

Paint-matching is the step that makes or breaks the result. Ford's colours shift in different light, so the FRP flares should be sprayed against your car's exact code, not an approximate match, or the widened sections will read as a slightly different shade. Done properly, the flares vanish into the bodywork and only the carbon pieces stand apart. If you want to plan the broader build, the Ford body kit range and the wider carbon fibre body kit catalogue cover complementary parts.

Frequently asked questions

Will this kit fit my Mustang's year and engine?

The CMST widebody kit is designed for the 2015-2017 S550 Ford Mustang and fits both the 2.3 EcoBoost and the 5.0 V8 GT. The pieces are cut to the S550's body, so check that your Mustang is that generation before ordering. Later facelift Mustangs have different front and rear bumpers, so the lip and bumper pieces are matched to the 2015-2017 car.

Can I get the kit in my car's colour?

Yes. The FRP arches, fenders and front bumper ship primed and are designed to be painted to your Mustang's exact colour code by a body shop, which is why the kit looks right in silver, green, grey, red or orange. The carbon pieces — front lip, bonnet, side skirts, rear diffuser and wing — keep their woven 2x2 twill finish under clearcoat and are not painted, so every build shares the same carbon accents over whatever body colour you choose.

Do the widebody arches need cutting or guard rolling?

The arches mount to the body and widen the track, so fitment is a workshop job rather than a simple bolt-on. Depending on your wheel and tyre size and offset, the fitter may need to roll or trim the inner guard so the tyre clears through full suspension travel and steering. We recommend professional fitment so the arches align cleanly and clearance is correct.

What wheels and tyres suit the widebody?

Because the arches push the track out around 5cm at the front and 6cm at the rear, the kit is built for a wider wheel and tyre package, typically 20-inch forged wheels with an offset chosen to fill the new arches. The right setup sits the tyre correctly within the flare and keeps clearance through travel and lock. Your fitter can confirm the exact width and offset for your car and ride height.

Do I need professional fitment?

We strongly recommend it. A widebody conversion involves mounting and aligning the arches, painting the FRP to your exact code, test-fitting the carbon aero for even gaps, and confirming wheel and tyre clearance. A workshop experienced with widebody and carbon work will deliver a factory-grade result and colour-match the painted pieces so the flares integrate with the body.

Ready to build a widebody S550? Explore the full CMST range at AME Motorsport, choose the pieces that suit your Mustang, and our Australian team can help you plan fitment, paint-matching and the right forged wheel package.