CMST 20-Inch 2-Piece Forged Wheels for Mustang
CMST's 20-inch 2-piece forged wheels for the widebody Ford Mustang (S550, 2015-2017) are forged from 6061-T6 aluminium with the spoke face and outer barrel formed as a single piece, then bolted to a separate inner barrel. CMST drew three 20-inch designs specifically for the widebody Mustang — the CT203 six-spoke, the CT205 multi-spoke and the CT211 five-spoke with a carbon-look lip — each CNC-machined for a precise finish and offered in custom colours. The result is a wheel built to hold its shape under hard rear-drive acceleration while filling the wider arches of a flared S550.
- Vehicle: Ford Mustang (S550, 2015-2017), set up for the widebody car
- Fitment: Staggered, with wider rears; offset and width matched to the widebody arches and tyre package
- Construction: 2-piece forged, 6061-T6 aluminium, T6 heat-treated, fine CNC surface finishing
- Sizes: Buildable 18-22 inch, in 1-piece and 2-piece; the 20-inch is featured here
- Designs: CT203 (6-spoke), CT205 (multi-spoke), CT211 (5-spoke, carbon-look lip)
- Finishes: Custom colours to order, including a made-to-order bright-red set
What CMST forged wheels are
CMST forged wheels are made from a solid billet of aircraft-grade aluminium that is pressed into shape under heavy load, rather than poured into a mould. For the widebody Mustang, CMST produced three 20-inch designs as a 2-piece build: a forged spoke face and outer rim joined to a separate inner barrel. The brief behind them was twofold — keep the wheel stable under the load a powerful rear-drive car puts through the contact patch when it launches, and give owners a face and finish worth looking at. AME stocks these through the CMST forged wheels for Ford range, alongside the wider CMST catalogue.
Forged 6061-T6 construction
The material is 6061 aluminium in the T6 temper, a common alloy for performance wheels because it balances strength, ductility and weight. The blank is forged — squeezed into shape under thousands of tonnes of pressure — and then given a T6 heat treatment, which solution-treats and artificially ages the metal to reach its rated hardness. Forging matters because of what it does to the grain. Casting leaves a relatively random internal structure with the small voids that come from molten metal cooling; forging compresses and aligns the grain flow along the shape of the wheel, which lifts the strength-to-weight ratio. In practice that means a forged wheel can carry the same load as a cast one with less material, so it ends up lighter at a given strength, or stronger at a given weight. Each wheel is then CNC-machined for a precise, jewellery-like surface before finishing.
1-piece vs 2-piece construction
CMST builds forged wheels in both 1-piece and 2-piece forms, and the choice changes how the wheel is made, how it can be specified and how it is repaired. A 1-piece wheel is forged and machined as a single monobloc. A 2-piece wheel splits the wheel into a forged centre-and-outer section and a separate inner barrel that bolt together, which opens up the width, offset and lip options a widebody car often needs.
| Aspect | 1-piece forged | 2-piece forged |
|---|---|---|
| How it is made | Single forged monobloc, machined from one billet | Forged sections bolted together (here, face-and-outer barrel plus inner barrel) |
| Custom width and offset | Fixed by the forging; fewer combinations | Adjustable by changing barrels, so width and offset can be tuned to the arches |
| Lip and refinish | Whole wheel must be refinished together | Lip and hardware can be refinished or repaired separately |
| Weight | Usually the lightest option, no joining hardware | Slightly heavier due to the barrel join and bolts |
| Cost | Generally lower for a standard fitment | Higher, with more bespoke sizing and finish choice |
For a widebody S550 the 2-piece build is usually the better fit, because the flared guards call for specific widths and offsets that a fixed monobloc cannot always reach. An owner chasing the absolute lightest wheel for a standard-bodied car, by contrast, may prefer the 1-piece. Both share the same forged 6061-T6 base.
The one-piece face-and-outer-barrel design
The structural detail that defines these wheels is where CMST splits the two pieces. Many 2-piece wheels join the centre disc to a barrel right behind the spokes; CMST instead forms the spoke face and the outer barrel as a single piece, then bolts the inner barrel on behind it. The reason is the outer lip. The outer rim is the part most exposed to kerb strikes and the highest cornering loads, and a join line sitting there is a weak point. By carrying the outer barrel out of the same forging as the spokes, the lip stays continuous and strong, with no seam where it is hit hardest, while the separate inner barrel still gives the width and offset flexibility of a 2-piece wheel. It is a way to keep the styling freedom of a built wheel without trading away outer-lip strength.
Designs and finishes
Three faces were drawn for the widebody Mustang, each a different spoke count and character. All can be ordered in custom colours, so the same design can read as subtle or loud depending on the lip and face combination.
CT203 six-spoke
The CT203 is a clean six-spoke face, the design CMST showed on the orange widebody Mustang and the one most often built for it. Its broad spokes suit a colour-split finish, where a coloured outer lip frames a contrasting face. One owner ordered a bright-red set, made to order, which is the example CMST features. The six-spoke layout also leaves the brake calipers visible, which matters on a car with the larger brakes the widebody invites.
CT205 multi-spoke
The CT205 is a denser multi-spoke design. The thinner, more numerous spokes give a more intricate, technical look than the CT203 and catch light differently across the face. It suits owners who want detail in the wheel itself rather than a bold colour split, though it takes custom colours just the same.
CT211 five-spoke with a carbon-look lip
The CT211 is a five-spoke face paired with a carbon-look lip. To be clear about what this is: the wheel is still a forged 6061-T6 alloy, and the carbon appearance is in the lip finish rather than a structural carbon-fibre barrel. The five-spoke face is the most classic of the three shapes, and the carbon-look lip gives it a darker, motorsport-flavoured edge. If you are after a genuine carbon barrel rather than a carbon-look finish, AME also stocks true carbon fibre wheels as a separate option.
Sizing and fitment on a widebody Mustang
The S550 widebody is exactly the kind of car a 20-inch 2-piece forged wheel is built for. A widebody conversion pulls the guards out over a wider track, and those bigger arches want a bigger wheel and tyre to fill them; a 20-inch diameter sits right in that range and also clears the larger brake packages owners tend to fit. A rear-drive Mustang puts its power down through the rear axle, so a staggered fitment — wider wheels and tyres at the rear than the front — gives the back end more grip for traction while keeping the steering crisp at the front.
The detail that has to be right is the offset and width. On a widebody car the wheel has to fill the flared arch without the tyre fouling the guard, the suspension arms or the inner liner through full bump and steering lock, and that envelope changes with the specific Ford Mustang widebody kit fitted. This is where the 2-piece build earns its place: the barrels can be specified to land the face and lip exactly where the arch wants them. CMST can build these wheels from 18 to 22 inch, so the 20-inch is a starting point rather than the only option, and the final spec should be confirmed against the car's arches and tyre choice before the order is placed.
Weight, ride and handling
The reason to forge a wheel, beyond looks, is mass in the right places. A wheel is unsprung weight — it is not carried by the springs — and it is also rotating mass, so it resists both the suspension's movement and the engine's effort to spin it up. Taking weight out of the wheel therefore does more than the same saving elsewhere on the car. Less unsprung mass lets the suspension react faster to bumps, keeping the tyre in better contact with the road for grip and a more settled ride. Less rotating mass means the engine has less inertia to overcome, which sharpens both acceleration and braking, and the lighter wheel changes direction more readily, which the driver feels as quicker steering. A forged 6061-T6 wheel delivers those savings without giving up strength, which is the balance CMST is aiming for: the highest safety standard paired with serious lightweighting. We are not quoting specific weights or load ratings here, because those depend on the exact size and spec built, but the direction of the benefit is consistent for any forged wheel over a heavier cast one.
Frequently asked questions
Will these CMST wheels fit my Mustang?
They are designed around the S550 Mustang, including the widebody car, but fitment always comes down to three things: the bolt pattern (PCD), the offset and the width. The S550 uses a 5x114.3 bolt pattern, which these wheels are built to, but a widebody car needs different offsets and widths from a standard-bodied one to fill the flared arches without fouling. Confirm your exact body, arch and tyre setup with AME so the offset and width are specified correctly before the wheels are made.
Should I choose 1-piece or 2-piece?
For a widebody S550, the 2-piece is usually the better choice because the barrels can be set to the exact width and offset the wider arches need, and the lip can be refinished or repaired on its own later. A 1-piece forged wheel is typically the lightest and a little cheaper, which can suit a standard-bodied car on a more common fitment. Both use the same forged 6061-T6 base, so the decision is about adjustability and finish rather than raw strength.
What sizes and colours can I get?
CMST can build these forged wheels from 18 to 22 inch, in 1-piece or 2-piece, with the 20-inch the size featured for the widebody Mustang. Custom colours are part of the offer — the bright-red made-to-order set is one example — so the face and lip can be finished to suit the car, including colour-split looks and the CT211's carbon-look lip. Confirm the current options with AME when you specify the build.
Are forged wheels really stronger and lighter than cast?
For a given size, yes. Forging compresses and aligns the aluminium's grain structure, where casting leaves a more random structure with small voids, so a forged wheel reaches a higher strength-to-weight ratio. That lets it be lighter at the same strength, or stronger at the same weight, compared with a cast wheel. The exact figures depend on the design and size, which is why CMST builds rather than mass-casts these.
Do they suit the 2.3 EcoBoost and 5.0 GT brakes?
The 20-inch diameter is chosen partly for brake clearance, and the open spoke designs help the calipers sit behind the wheel. Both the 2.3 EcoBoost and the 5.0 GT, and any larger aftermarket brake kit, need their caliper and disc dimensions checked against the chosen wheel's barrel and spoke clearance. Give AME your brake setup when ordering so the fitment is confirmed for your car.
Do I need professional fitting, TPMS and tyres sorted?
Yes. These wheels should be mounted, balanced and torqued by a tyre shop, with tyres chosen to match the final width and the car's arches. The S550 runs tyre-pressure monitoring (TPMS), so the sensors need to be fitted or transferred to the new wheels and reset. Having a workshop handle the fitting also lets them confirm clearance through full suspension travel and steering lock on the widebody.
Build your widebody Mustang on CMST forged wheels
If you are putting a set of forged wheels under a widebody S550, AME Motorsport can supply the CMST CT203, CT205 or CT211 in the size, offset and custom colour your build needs. Start with the CMST forged wheels for Ford range to see the designs, browse the full CMST catalogue for matching parts, and get in touch with your arch and tyre details so the 2-piece spec is confirmed before the wheels are built.