Every part shown is manufactured under exacting standards to exceed factory specifications. dSeiki can support custom applications beyond what is pictured here.
The parts featured below represent current production across four engine systems: drive and accessory, valvetrain, reciprocating assembly, and lubrication. Applications span the 930/935, the 959, the latest 9A1 variants, and most vintage air-cooled engines.
Where a part is shown for a specific listed application, it has been manufactured and proven in service. dSeiki also performs complete cylinder head reconditioning to factory guidelines — new guides, valves, and all sealing surfaces machined to specification. If you do not see your application listed, contact us to discuss what is possible.
DLC-coated billet rockers, application specific dual valve springs, and newly manufactured valves using modern materials and coatings.
DLC-coated billet rocker arm for vintage air-cooled engines. Offered in ultra light racing configuration with a lash cap, or light street configuration with an adjustable foot.
Dual valve spring rated for vintage air-cooled applications running up to 14 mm of valve lift. Uses OE seats and custom retainers. Sets are available and ready to ship immediately.
Custom springs are available for racing!
Dual valve spring rated for the modern 911 GT3 9A1 engine, supporting up to 13 mm of valve lift. Uses OE seats and retainers. Sets are available and ready to ship immediately.
Custom springs are available for racing!
Engine valve shown for the 959. Any Porsche valve stem diameter and profile can be manufactured to order — We can also supply uprated materials for lighter mass, lower friction or higher thermal capability. Please provide your requirements and we will create the right combination of materials, coatings and shapes to support your needs.
Hard anodized aluminum pulleys and a rebuildable tensioner, manufactured to factory 930/935 specifications. Color is per original; Look and function are correct.
Multi-groove serpentine crank pulley, hard anodized aluminum, manufactured to factory 935 specification.
Vee groove alternator pulley, hard anodized aluminum, manufactured to factory 935 specification.
Combination pulley integrating two drive functions in a single hard anodized aluminum component, to factory 935 specification.
Rebuildable tensioner with hard anodized aluminum belt-contact surfaces. Designed for service rather than replacement.
GT3 pistons, and an improved oil pump shaft designed around a splined drive interface.
Piston shown for the 911 GT3 (9A1) application. Custom bore, compression, and dome configurations are supported for other Porsche applications — provide your requirements for review.
A splined gear and shaft replaces the 9A1 factory three-lobe drive shape on this oil pump shaft, improving torque transmission through the pump under demanding conditions.
Three-lobe (poly) drive interface
Splined gear interface
The splined interface increases margin against torque-related failure, reducing the risk of a drive failure that interrupts oil pump operation. No block modifications are required, parts drop in and are secured with the factory bolt.
Complete cylinder head reconditioning to Porsche factory guidelines — new guides, valves, and all mating surfaces machined to specification.
Cylinder head shown is a Porsche 959 unit, fully reconditioned and ready to install. The same process is applied to most Porsche air-cooled and water-cooled heads — 930, 935, 959, 9A1 variants, and vintage engines.
Every head is reconditioned to Porsche factory specifications: new valve guides installed to factory interference and finished to stem clearance, new valves fitted to the correct stem diameter and head profile for the application, and all three sealing surfaces — intake port, exhaust port, and cylinder deck — precision-machined to factory flatness and finish requirements.
Installed to factory interference, finished to stem clearance specification
Correct stem diameter, head profile, and material for the application
Seat machining to factory width and angle specifications
Precision-machined to factory flatness and surface finish for correct gasket sealing
Tell us which components you're interested in having custom made, along with your application, and we will follow up with pricing and lead time.
For urgent inquiries or ongoing programs, reach us directly.
info@dseiki.comdSeiki Corporation