Material guide
Material Grades Explained
Most vehicles are tooled in more than one grade, so the same mold can serve a show build and a volume order. The grade decides three things a buyer actually feels: what it weighs, what it looks like straight out of the box, and whether it needs paint before it goes on a customer's car.
Five grades side by side
| Grade | Process | Weight | Finish on arrival | Typical use |
|---|---|---|---|---|
| DRY CARBON | Prepreg, cured under heat and pressure | Lightest | Finished twill or forged weave | Show and track builds |
| VACUUM CARBON | High-temperature vacuum forming | Light | Gloss clear coat | The volume carbon grade |
| FRP | Glass fiber with resin primer | Moderate | Primed, paint-ready | Bumper shells, arch sets |
| ABS | Vacuum-formed sheet | Moderate | Gloss or matte black, molded in | Volume kits, no paint needed |
| PP | Injection molded | Heaviest | Gloss or matte black, molded in | Impact-tolerant OE-style parts |
Not every part exists in every grade — a bonded arch set and a bootlid spoiler do not have the same production route. The grades available for a given part are confirmed on the quotation.
Definitions
What the grades actually are
Trade buyers get asked these questions by their own customers, so here is the plain version.
- 01
Dry carbon
Prepreg — the carbon cloth arrives already impregnated with resin in a controlled ratio — is cut, laid into the mold by hand and cured under heat and pressure. Because no extra resin is added during lay-up, it is the lightest of the five and the weave comes out of the mold already finished, in twill or forged pattern. It is the grade for show cars, track cars and the parts a customer wants left bare.
- 02
High-temperature vacuum carbon
Often called wet carbon in the trade. Resin is applied during lay-up and the part is formed under vacuum at high temperature, then finished with a gloss clear coat. It is slightly heavier than dry carbon and costs less to produce, which makes it the grade most volume carbon orders are built in. Visually it is a gloss carbon surface; the difference from dry carbon is in weight and in how the weave sits under the coat.
- 03
FRP
Glass fiber and resin, supplied primed. FRP arrives paint-ready, not finished — the installer or the shop paints it to the car's color. It is the sensible route for large bumper shells and wide-arch sets, where a painted body-color finish is what the customer wants anyway and carbon would only add cost.
- 04
ABS
Vacuum-formed sheet, molded in gloss or matte black. The color is the material, so the part goes on the car straight out of the box with no paint step. This is the volume grade for shops that want to fit and invoice on the same day.
- 05
PP
Injection molded, the heaviest of the five and the most impact tolerant — the same family of plastic most OEM bumpers and lower trim are made from. Used where the part will take stone chips and kerb contact and needs to behave like a factory part rather than a show part.
Choosing a grade
Start from what the end customer is buying, not from the material name.
| If the customer wants | Grade | Because |
|---|---|---|
| BARE CARBON LOOK | Dry carbon | Comes out of the mold finished — no paint, no clear coat step, lightest option |
| CARBON, ON BUDGET | Vacuum carbon | Gloss carbon surface at the grade most volume orders run in |
| BODY-COLOR KIT | FRP | Arrives primed and paint-ready, so the paint step was always going to happen |
| FIT AND INVOICE TODAY | ABS | Molded black, no paint step, no drying time |
| DAILY-DRIVEN CAR | PP | Impact tolerant and OE-like — built for kerbs and stone chips |
Mixing grades within one kit is normal: an FRP bumper shell with dry carbon detail parts is one of the most common combinations we quote.
What arrives, and what still has to be done
Carbon parts — dry or vacuum — arrive finished. FRP arrives primed and needs paint. ABS and PP arrive in molded gloss or matte black and need nothing. Plan the shop time accordingly: a kit that mixes FRP shells with carbon detail parts still needs a paint booth for part of it.
Every kit is supplied with the hardware and instructions needed to fit it, and installation videos are available for most vehicles. Orders ship in CMST-branded packaging with a product label and a parts pack, so a shortage is visible at first opening and a distributor can prove what is genuine.
Standard lead time is 7–20 days. Lead time is confirmed against the production schedule when the order is placed, and peak-season extensions are flagged before you confirm — never after.
Questions buyers ask
Is dry carbon stronger than vacuum carbon?+
The honest answer for a body panel is that the difference a customer notices is weight and surface, not strength. Dry carbon is lighter because the resin ratio is controlled in the prepreg rather than added by hand during lay-up. For exterior aero parts, both grades are made to the same fitment and surface standard.
Does FRP have to be painted?+
Yes. FRP ships primed and paint-ready. If the customer does not want a paint step, quote ABS instead — it is molded in gloss or matte black and goes on the car as delivered.
Can one kit mix grades?+
Yes, and it is common. A typical widebody order runs FRP for the large shells and arches with dry carbon for the lip, canards and diffuser. Tell us the split when you request the quote.
How is the surface checked before it ships?+
Every part is inspected against a written surface standard: no pits, no whitening, no waviness, no wrinkling and no print-through. Parts that fail go back, they do not get packed.
What is the warranty on a carbon part?+
Carbon fiber parts are covered for three months from the date they are fitted; forged wheels are covered for five years. Where a claim is confirmed as a quality issue, CMST replaces the same part or compensates its equivalent value — freight is not covered. Liability is confirmed within one working day of the report. Full terms are on the warranty page.
Do you publish prices?+
No. CMST supplies tuning shops and distributors, and the price depends on grade, kit content and which trade tier you buy on. Minimum order is one piece — four for wheels — and orders can be mixed across vehicles, so a quote does not commit you to a pallet.
Send the vehicle and the grade
Quotes come back with kit content, the grades available for that part and a lead time. Tuning shops and distributors only.