Multi-pocket geometry
Internal pockets and webs reveal the machining detail within a complex structure.
PC · PRECISION CUSTOM
BILLET PISTONS · PRECISION CUSTOM
Precision custom development for billet piston projects. Bring your engine requirements, samples or design brief.
Discuss your PC project
BILLET · Geometry shaped by precision machining.
BILLET · MACHINED FROM SOLID
Actual JND billet piston photographs, exploring custom geometry and machining detail from crown to internal cavity.
Internal pockets and webs reveal the machining detail within a complex structure.
A closer view of the connections between the pin bosses, inner cavity and skirt.
Crown development considers combustion-chamber and valve geometry, with the final design agreed for each project.
A close view of internal contours, transitions and the visible toolpath texture.
These photographs show different structures from actual JND billet products. Material, specifications and engine suitability are confirmed for each project.
DESIGN TO REALITY
Explore the corresponding CAD model and physical product, with a closer look at the pin bosses, internal cavity and skirt.
A closer view of the crown profile and visible machining texture.
A close view of the internal structure and pin-boss connections.
TWO-STROKE · BILLET CUSTOM
These two-stroke billet pistons feature tall skirt profiles, illustrating a demanding custom machining project. Overall height, pin-bore layout and internal geometry guide the development of the machining approach.
See the development processA PROJECT, FROM START TO FINISH
This JND workflow example follows a piston-blank machining route. Billet projects use a separately agreed stock-preparation and machining plan.
CHOOSE THE RIGHT ROUTE
The manufacturing route is a design decision, not a substitute for a complete engineering brief.
Machined from solid stock. Discuss the design, quantity and material requirements before selecting this route.
A forged blank is machined to the agreed geometry. Blank availability and design requirements are part of the review.
Project availability and process selection require technical confirmation.
THE PC APPROACH
An ambitious engine project rarely starts with a standard answer. It starts with a goal, a set of constraints and the details that make that engine different. PC was shaped around that conversation.
From a billet piston brief to a specific crown, pin or ring requirement, the focus stays on the relationship between design and manufacture. Understand the application. Define the geometry. Work through the details.
Within JND, PC is the dedicated space for precision custom development — where a customer’s requirements guide the project rather than an off-the-shelf catalogue.
A STRONGER PROJECT BRIEF
Engine model, intended use and the development goal.
An existing sample, non-confidential dimensions or design requirements.
Approximate quantities, sample needs and your expected timeline.
PC / DETAIL IS THE DIFFERENCE
Actual billet-machined product details show the relationship between internal cavities, supporting webs and tool access.
Explore this detail ↗Tall profiles and deep internal features bring particular machining challenges. Discuss the geometry and manufacturing plan for your project.
Explore this detail ↗Crown shape and valve-relief areas are developed from the engine configuration, with final dimensions and clearances confirmed in the project.
Explore this detail ↗PIN SUPPORT & LUBRICATION

Standard-equipped models feature dual forced pin oil holes and accumulator grooves to support lubrication and stability at high engine speeds.
Applicable packages include 9310 nickel-alloy steel pins, a complete ring set and aluminium pin-boss support. The supplied components are specified with the piston.
Selected high-output applications offer or recommend HD pins, including project configurations targeting 600+ or 1,000+ hp. Suitability depends on the engine, loads and complete specification.
Features vary by model and application. Final alloy, components, clearances and installation requirements follow the confirmed product specification. Horsepower examples describe specific project configurations, not a universal piston rating.
SURFACE & FRICTION CONTROL

Molybdenum skirt coatings help reduce friction and improve running-in. Selected skirt-coating configurations also help control operating noise.
A range of surface treatments supports service life and reliability. The finish is selected with the material, running clearance and operating conditions.
PRECISION, PRESENTED.
Explore two exterior design concepts for a four-piston set, bringing PC’s precision custom identity to the final presentation.
A restrained navy palette gives the metallic PC identity and internal machining detail a clear focus.
Silver-white surfaces and a cropped product detail connect the packaging to the engineering behind it.
Packaging design concepts shown. Final format and specifications are agreed for each project.
PRECISION CUSTOM