Carbin Editor

May 6, 2026 · View on GitHub

The Carbin Editor page lets you open, inspect, edit, and rebuild .carbin scene files - the primary packaging format used by ForzaTech to describe a car's complete visual representation. A carbin file defines which .modelbin geometry files make up each named section of the car, how those sections behave at different upgrade levels, and scene-level properties such as the skeleton path, LOD flags, and build metadata.

The format is used by the game engine at runtime as CarScene to load and instance every visible part of the car, from the body shell and interior to swappable bumpers and spoilers.

Opening a File

Drag and drop a .carbin file directly onto the page.
Use the Open button in the toolbar (Ctrl+O).
Use the New button (Ctrl+N) to create a blank carbin pre-filled with Forza Horizon 5 defaults.

Button	Shortcut	Description
New	Ctrl+N	Create a blank carbin with default FH5 settings
Open	Ctrl+O	Browse and open an existing `.carbin` file
Save	Ctrl+S	Overwrite the original file with current edits
Save As	Ctrl+Shift+S	Write to a new file path
Close	Ctrl+W	Unload the current file and return to the empty state

The loaded file name and a status message are shown in the header. A progress banner appears while the file is being parsed or saved.

Page Tabs

Once a file is loaded the editor is split into three tabs:

Tab	Description
Configuration	Scene-level metadata, version, skeleton path, LOD flags
Standard Parts	Non-upgradable parts and their model references
Upgradable Parts	Parts with per-upgrade-level model variants and shared models

Configuration Tab

File Metadata

Displayed at the top of the tab after loading:

Field	Description
Scene Version	Version number read from the carbin binary header
Model Version	Version of the embedded model blob entries
Series	Whether the file was detected as Horizon or Motorsport, based on scene version

Scene Settings

Field	Description
Output Game Version	Dropdown selecting which game version to write when saving. Changes scene and model version numbers accordingly
Ordinal	Numeric identifier for this scene, used internally by the game
Scene Name	Short identifier string derived from the skeleton path (e.g. `CUSTOMCAR`)
Media Name	Asset media folder name used to build game paths (e.g. `CUSTOMCAR`)
Skeleton Path	Full in-game path to the `_skeleton.modelbin` file (e.g. `game:\media\cars\CUSTOMCAR\scene\_skeleton.modelbin`). This path is used by the engine to load bone data for animation and part attachment
Build Strict Mode	When enabled, the game will reject the carbin if any referenced asset is missing rather than silently skipping it

Supported Output Game Versions

Selection	Scene Version	Model Version	Series
Forza Motorsport 5	5	14	Motorsport
Forza Motorsport 6 / 7	5	17	Motorsport
Forza Motorsport 2023	10 - 11	21	Motorsport
Forza Horizon 2	5	15	Horizon
Forza Horizon 3 / 4	5	16	Horizon
Forza Horizon 5	6	18	Horizon

Level of Detail (LOD) Flags

A set of checkboxes controls which LOD levels are included when the scene is built. Each flag is a single bit in a 16-bit field written to the carbin:

Flag	Description
LODS	Shadow LOD mesh group
LOD0	Highest detail level (closest camera distance)
LOD1	Second detail level
LOD2	Third detail level
LOD3	Fourth detail level
LOD4	Fifth detail level
LOD5	Lowest detail level (furthest camera distance)

Typical configuration for Forza Horizon 5 has LODS through LOD4 enabled and LOD5 disabled.

Standard Parts Tab

Standard parts (called non-upgradable parts in the format) are car sections that have a fixed geometry that does not change with in-game upgrades. The entire car body, doors, trunk, interior, windows and similar components are stored here.

Parts List (left panel)

Lists all standard parts in the file. Each entry shows the part type name and the number of models attached to it.

Toolbar buttons:

Button	Description
Add	Add a new empty standard part defaulting to `CCarParts_CarBody` type
Remove	Delete the currently selected part and all its models
Convert	Move the selected part to the Upgradable Parts tab, adding a default stock upgrade entry

Part Configuration (right panel)

When a part is selected:

Field	Description
Part Type	Dropdown selecting the `CCarPartsEnum` value for this section (see part types below)
Version	Internal version number for this part entry, preserved from the source file for byte-accurate round-trips
Bounding Box	Expandable section showing Min/Max XYZ extents for the part, used by the engine for culling

Part Types Reference

The following CCarPartsEnum values are available:

Value	Name	Description
0	CCarParts_Engine	Engine geometry
1	CCarParts_Drivetrain	Drivetrain components
2	CCarParts_CarBody	Primary car body shell
3	CCarParts_Motor	Motor parts (electric vehicles)
4	CCarParts_Brakes	Brake geometry
5	CCarParts_SpringDamper	Suspension spring / damper parts
6	CCarParts_AntiSwayFront	Front anti-roll bar
7	CCarParts_AntiSwayRear	Rear anti-roll bar
8	CCarParts_TireCompound	Tire geometry
9	CCarParts_RearWing	Rear wing / spoiler
10	CCarParts_RimSizeFront	Front wheel rims
11	CCarParts_RimSizeRear	Rear wheel rims
12 - 33	CCarParts_Camshaft through CCarParts_Differential	Internal engine and drivetrain upgrade geometry
34	CCarParts_FrontBumper	Front bumper
35	CCarParts_RearBumper	Rear bumper
36	CCarParts_Hood	Bonnet / hood
37	CCarParts_SideSkirts	Side skirts
38	CCarParts_TireWidthFront	Front tire width geometry
39	CCarParts_TireWidthRear	Rear tire width geometry
40	CCarParts_WeightReduction	Weight reduction parts
41	CCarParts_ChassisStiffness	Chassis stiffness parts
42	CCarParts_Ballast	Ballast
43	CCarParts_MotorParts	Motor upgrade parts
44	CCarParts_WheelStyle	Wheel style geometry
45	CCarParts_Aspiration	Aspiration upgrade parts

Models (right panel)

When a part is selected its model list shows every .modelbin reference attached to it.

Each entry displays:

The .modelbin file name
The full in-game asset path (e.g. game:\media\cars\CUSTOMCAR\scene\body_a.modelbin)
The AO swatchbin path when one is assigned

Toolbar buttons next to the list:

Button	Description
Add	Browse for one or more `.modelbin` files to add to this part
Remove	Remove the selected model entry from the part
Set AO	Browse for a `.swatchbin` ambient occlusion texture to associate with the selected model
Move	Move the selected model to a different part in the list

Right-click a model entry to edit its model path or AO path directly as text.

Use the Search box above the list to filter by file name or game path.

The Model Version field next to the search box shows the version number of the selected model entry and can be edited for byte-accurate round-trips.

Material Indices

Below the model list, the Material Indices card shows the material name-to-index mapping for the selected model entry. These map material slot names (e.g. body_paint) to integer indices used by the material system.

Button	Description
Add	Add a new blank material index row
Remove	Remove the selected row
Load	Import material names from a `.modelbin` or `.carbin` file. When loading from a carbin, a selector dialog lets you pick which model to copy from

Each row has an editable material name field and a numeric index value.

Transform and Bone

Below the material indices, the Transform and Bone card shows the world-space position and attachment settings for the selected model:

Field	Description
Bone Name	Name of the skeleton bone this model attaches to (default is root)
Bone ID	Numeric bone index
Snap to Parent	When enabled the model snaps to the parent bone transform
Pos X / Y / Z	World-space position offset for the model
Scale	Uniform scale factor

Render Properties

The Render Properties card controls how the model is drawn:

Field	Description
Draw Groups	Checkboxes for Exterior, Cockpit, Shadow, Hood, Windshield Reflection, Driverless Cockpit, Windshield Reflection Driverless Cockpit, and Proxy LOD. Controls which rendering passes include this model
Receives Impact Mask	Model receives bullet or debris impact decals
Receives Splatter Mask	Model receives mud / water splatter
Receives Damage	Model participates in deformation damage
Receives Dirt	Model receives dirt accumulation
Receives Oil	Model receives oil splatter effects
Receives Rubber	Model receives tyre rubber marks
Receives Rain	Model receives rain wetness effects
Is Interior Windshield	Marks the model as an interior-facing windshield surface

Droppable Part Settings

When a model is configured as a droppable part (a panel that detaches on collision damage):

Field	Description
Is Droppable	Enables detachment behaviour
Drop Value	Threshold value controlling when the part detaches
Drop Part ID	Hex identifier linking this model to a physics drop part definition
Break Amount	Force amount required to break this part free

Upgradable Parts Tab

Upgradable parts are sections of the car that have multiple geometry variants, one per upgrade level. Examples include front and rear bumpers, hoods, and side skirts. The game selects which variant to render based on the installed upgrade level.

Parts List (left panel)

Lists all upgradable parts. Each entry shows the part type name.

Toolbar buttons:

Button	Description
Add	Add a new empty upgradable part defaulting to `CCarParts_FrontBumper`
Remove	Delete the currently selected upgradable part
Convert	Move the selected part back to the Standard Parts tab (upgrade IDs are cleared)

Upgrades

When an upgradable part is selected, the Upgrades list shows each upgrade level entry.

Toolbar buttons:

Button	Description
Add	Add a new upgrade entry
Remove	Remove the selected upgrade entry

Each upgrade entry has:

Field	Description
Version	Internal version number for this upgrade entry
Level	The upgrade tier this entry represents (0 = stock)
Is Stock	Marks this entry as the default stock configuration
ID	Unique identifier for this upgrade, referenced by shared model entries
Car Body ID	Links this upgrade to a specific car body database entry
Parent Is Stock	Indicates the parent upgrade is stock
Bounding Box	Min/Max XYZ extents for this upgrade level's geometry

Shared Models

Below the upgrades list, the Shared Models section lists models that are used across multiple upgrade levels. Each shared model entry has a list of Upgrade IDs specifying which upgrade levels it appears with.

Toolbar buttons:

Button	Description
Add	Browse for a `.modelbin` to add as a shared model
Remove	Remove the selected shared model
Add Upgrade ID	Add an upgrade ID reference to the selected shared model
Remove Upgrade ID	Remove the selected upgrade ID from the shared model

The model detail fields (material indices, transform, bone, render properties, droppable settings) work identically to those in the Standard Parts tab.

Version and Series Detection

After loading, the Configuration tab shows the detected Scene Version and Model Version read from the binary. The editor uses these to determine the correct enum encoding for part types:

Scene version 6 indicates Forza Horizon 5
Scene version 10 or higher indicates Forza Motorsport 2023
Scene version 5 is shared between older Motorsport and older Horizon titles; the model version is used to narrow it further
Part type values are encoded differently in older versions (CCarParts_EnumV1 vs CCarParts_Enum). The editor handles this automatically during both read and write

Saving Changes

Use Save (Ctrl+S) to overwrite the original file in place, or Save As (Ctrl+Shift+S) to write to a new path. The Output Game Version dropdown on the Configuration tab controls which version numbers are written to the file. Changing this dropdown before saving is how you retarget a carbin to a different game.

Back up the original .carbin before saving. An incorrect model path, wrong version number, or a missing skeleton path can prevent the game from loading the car entirely.

Converting a .carbin

To convert a .carbin to a different game version with full path rewriting and blob header updates, use the Conversion Tool page. The Carbin Editor can change the version numbers manually via the Output Game Version dropdown but does not rewrite game paths or model blob internals. The Conversion Tool handles the complete transformation in one step.