Carbon Fiber Side Skirts Installation Guide: Factory Screws, Clips & 3M Tape

Side skirts are the longest carbon fiber parts we ship — and the most satisfying to install, because every mounting point already exists on your car. There is no drilling, no bumper removal, and no wiring. The whole job is patience, alignment, and not overtightening the bottom screws.

As the manufacturer, we build two designs: full replacement skirts that take the place of the OEM rocker panels, and add-on skirt extensions that mount over the factory rockers. Both reuse factory mounting points. This guide covers both, with the same procedure our engineers follow.

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Carbon fiber side skirt mounting points and screw layout diagram

Step 0: Know Which Design You Have

	Replacement Skirt	Add-On Extension
What it is	Replaces the OEM side skirt	Overlays the factory rocker panel
OEM skirt removal	Yes	No
Mounting	Factory screws + plastic clips (+ tape on top edge)	OEM clips + screws + 3M VHB tape
Time	1–1.5 hrs per side	40–60 min per side
DIY?	Yes	Yes

If your package contains a pair of full rocker-length panels with clip slots on the back, it is a replacement — that is Method A. Slim blades or fins that sit under or beside the factory rocker are extensions — Method B.

Tools & Prep (Both Methods)

Isopropyl alcohol or acetone, clean microfiber cloths
Plastic trim removal tools for the OEM clips
Socket/ratchet set or a power driver — low torque setting only
A low-profile jack and jack stands, or ramps — you need the full rocker accessible
Painter’s tape for alignment marks
A heat gun in cold weather — 3M tape bonds best above 15 °C / 59 °F
A friend: a side skirt is a two-person part to align

Full prep rules — cleaning, test fitting, temperature — are in our general installation guide.

Method A: Full Replacement Skirts

This is how most of our BMW skirts mount, e.g. the F92/F93 M8 side skirts: the OEM skirt comes off, the carbon skirt clips and screws into the same points — 16 factory M6×16 screws along the bottom edge, plastic clips, and 3M VHB tape sealing the top edge.

The procedure (per side):

Lift the car and support it on stands or ramps. Keep the wheels on — you will check arch clearance later.
Remove the OEM side skirt: bottom screws first, then release the clips along the rocker with trim tools, working front to back. Keep every screw and clip.
Transfer any reusable clips to the carbon skirt and test-fit it against the rocker: clips aligned, front and rear ends flush with the wheel arches.
Clean and prime the top contact edge (alcohol, then primer inside the tape zone only). ⚠️ Surface primer can dull or scratch visible paint if you spread it wide.
Set the skirt on the clips, press the top edge tape zone from the center outward, then drive the factory bottom screws at the designated points — center first, working outward. Snug, not tight.
Repeat on the other side, then lower the car and check both sides for left-right symmetry in daylight.

Pressing a carbon fiber side skirt onto the rocker panel with 3M tape

Some models are pure clip-and-screw with no top tape (e.g. our G80 M3 skirts: factory screws plus 18 plastic buckles per side) — same order, minus the primer step.

Method B: Add-On Skirt Extensions

Extensions mount over the factory rocker — no OEM panel removal. Our Ford Mustang GT extensions are typical: 16 OEM clips at the factory mounting points, double-sided tape along the blade, and screws driven with a power tool at the designated points.

Remove the genuine bolts at the designated install points along the rocker.
Dry-fit the extension and mark both ends with painter’s tape. Check the gap to the front and rear wheel arches.
Clean the rocker surface with alcohol; apply primer inside the tape zone only.
Peel the tape film slightly outward at each end — tabs out, don’t remove yet. Set the extension on your marks.
Once the fit is perfect, pull the film tabs out while pressing the blade down, 30–60 seconds per section.
Drive the screws and seat the OEM clips at the designated points with a power tool on low torque.

Side skirt tape zone and OEM clip layout diagram

Multi-section designs (e.g. our BMW G90 M5 skirts, 24× M6×16 screws + tape, upper-edge clips that lock into the mounting points) follow the same logic: position left-right symmetric first, temporarily fasten, then torque everything per the install-point map.

Time & Difficulty by Vehicle

Vehicle	Design	Hardware	Time
BMW F92/F93 M8	Replacement	16 screws + clips + tape	1–1.5 hrs/side
BMW G80 M3 / G82 M4	Replacement	Screws + 18 plastic buckles	1 hr/side
BMW X3M/X4M/X5M	Replacement	18 screws + clips + tape	1–1.5 hrs/side
BMW G90 M5	Add-on, multi-section	24 screws + clips + tape	1 hr/side
Ford Mustang GT	Add-on extension	16 OEM clips + tape	40–60 min/side

The 5 Mistakes That Ruin Side Skirt Installs

Breaking the OEM clips during removal — pull the skirt straight out, not down; a snapped clip leaves the carbon skirt with one less mounting point.
Skipping left-right symmetry checks — mount both sides to the same reference (e.g. distance from the arch lip), or the car looks lopsided from behind.
Overtightening the bottom screws — carbon cracks around the hole before it feels tight. Low torque, snug only.
Taping a dirty rocker — road film lives on the rocker panel. Alcohol-wipe twice; this is the dirtiest surface on the car.
Lowering the car before the tape cures — keep it on stands for at least a few hours; full cure is 24–72 hours.

After Installation

24–72 hours: no car washes or highway speeds while the tape cures.
Re-check bottom screw tension after the first week, then monthly.
Avoid automatic car washes with side brushes — they catch the skirt edge.
Jacking note: always lift on the factory jacking points, never under the carbon skirt.

FAQs

No. All install points are reachable with the wheels on — you only need the rocker area accessible, which stands or ramps provide. Turning the front wheel outward helps reach the forward-most screw.

Slightly — typically 10–20 mm depending on the design. Our skirts follow the factory rocker line, so speed bumps and driveways that cleared before will still clear. Treat steep ramps with the same care you give a front lip.

Both, by design. The screws and OEM clips carry the structural load; the 3M VHB tape seals the top edge against water and prevents vibration. Never skip the tape zone on a design that calls for it.

Yes — the design assumes it. Keep everything when the OEM skirt comes off. Standard sizes are available at hardware stores if a clip breaks.

Stop before taping or driving any screw. Send us photos of the fitment plus your model and year — our team checks every case, and manufacturing deviations are covered by our after-sales policy. See how we guarantee fitment.

Plenty — most bolt-on and stick-on carbon parts are DIY-friendly with basic tools. Popular next installs after this one: Front Lip, Rear Diffuser, Mirror Cover installation guides. All of them follow the same prep rules in our general installation guide.

Shopping for side skirts? Browse all carbon fiber side skirts — applications for BMW G80 M3, BMW M3, BMW M5 and Ford Mustang. Every kit ships with the clips, screws and 3M tape needed for that specific part.

More Carbon Fiber Installation Guides

Author: He Dong

He Dong has spent 20+ years doing what he loves most — making cars and bikes faster, sharper, and better looking.

As an Automotive & Motorcycle Engineering Specialist, he’s worked on everything from engine builds and chassis tweaks to track machines and custom aftermarket projects. If it has wheels and an engine, he’s probably taken it apart and made it better.

These days he focuses on the aftermarket world, where good engineering meets real-world budgets — and he’s not shy about calling out parts that look great in photos but don’t perform.

This blog is where he shares what’s worked, what’s failed, and what he’s learned along the way. Honest, hands-on advice, straight from someone who’s done the work himself.

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