Diagnostics
Identify the engine, inspect condition and establish compatibility before recommending a build.
ENGINE-FIRST CUSTOM BUILDS
3.9L Cummins 4BT
Engine serial number, CPL, injection system, governor and accessories guide the build. We assess engine dimensions, operating characteristics and drivetrain compatibility for the proposed installation.
4BT platform · inline-fourEngine · transmission · controls
Configuration shown is representative; build components are confirmed by quote.
YOUR ENGINE · YOUR PROJECT
A complete system.
Built around your goals.
Start with the work you want to discuss. We can assess an engine you already own, help source a powertrain, or plan the engine, transmission and controls together.
THE BOMBPROOF APPROACH
Understand first.
Build for the long run.
We preserve what is serviceable, explain each recommendation and plan the powertrain as a whole.
Prevention
Review fuel delivery, lubrication and heat management to protect usable components.
Restoration
Restore mechanical function and address underlying issues before adding performance.
Maintenance
Document the completed system and create a service plan for its actual use.
Performance
Match upgrades to a healthy engine, the recipient chassis and realistic project goals.
BEFORE WE SPECIFY PARTS
Good builds
start with context.
Share the engine identity or serial number, what you already have, the proposed installation and how you intend to use it. Photos of the engine, harness and transmission help us assess completeness.
Know the engine.
Engine serial number, CPL, injection system, governor and accessories guide the build. We assess engine dimensions, operating characteristics and drivetrain compatibility for the proposed installation.
Match the whole powertrain.
Transmission, adapters, controls, wiring, cooling, fuel supply, mounts and driveline requirements are reviewed together. Standalone controls are selected for the exact engine and permitted application.
Agree on a written scope.
We separate inspection, sourcing, restoration and installation so you can see what is included. Parts availability, project acceptance and schedule follow review.
Review our powertrain sourcing terms and competition project policy. Emissions and use requirements are assessed for the complete installation.
Have an engine in mind?
Start a project inquiry with 3.9L Cummins 4BT already attached.