Four-Stroke Engine Specification Example for Aftermarket Retail: Two-Piece Construction
Four-Stroke Engine Specification Example for Aftermarket Retail: Two-Piece Construction
This is a worked specification for four-stroke engine in a two-piece construction programme. It is the document we would send a buyer who asks what exactly they are getting: the material, the dimensions that are actually controlled, the finish, and the checks that happen before anything is packed.
The two-piece construction version exists because the duty cycle on aftermarket retail is not the same as on a showroom vehicle. Where the two are specified identically, something fails later — usually inconsistent hardness between lots.
Example specification
| Item | Four-Stroke Engine |
|---|---|
| Application | Aftermarket Retail |
| Version | Two-Piece Construction |
| Base material | Zinc Plated Steel |
| Controlled dimensions | 6 key dimensions, recorded per lot |
| Tolerance band | ±0.5 mm |
| Finish | zinc plated |
| MOQ | 3,000 pieces per specification |
| Sampling | 14 working days, 5 days per revision |
| Compliance | ISO 9001 |
How the example is built up
- Start from the duty cycle, not from the catalogue photograph.
- Fix the base material in writing — Zinc Plated Steel, in this example.
- List the dimensions that are actually controlled and the tolerance on each.
- Name the finish and what it has to survive.
- State the inspection level and who pays when a lot fails.
Processes involved
- assembly line testing
- gravity casting
- CNC machining
- die casting
- precision stamping
- sintering
Where this example applies
Programmes that run two-piece construction most often specify this build for aftermarket retail. Related applications include dealership service, utility trailers, assembly programmes, light trucks, boat trailers.
Checks before packing
- Dimensional report against the approved drawing.
- AQL 4.0 sampling on the finished lot.
- Finish inspection under agreed lighting.
- Carton drop test on the first lot of a new packing specification.
Questions buyers ask
What testing is included?
Standard lots ship with dimensional and hardness reports. ISO 9001 documentation is issued with the shipment when your market requires it.
What happens if a lot fails inspection?
The lot is re-inspected against the golden sample, and replacement pieces ship on the next available booking at our cost.
What is the minimum order quantity?
The standard MOQ is 3000 pieces per specification. Mixed sizes inside one shipment are accepted once the total reaches that figure.
Do you handle mixed containers?
Yes. Most programmes consolidate several part numbers into one container to keep freight sensible at 3000 pieces per line.
Send the part number, the annual volume and the target market, and we will come back with a specification and a sampling plan.
