Porsche 911 Turbo (930) 1975–1989 Workshop Manual Set (P/N WKD 481 321)

The repair-group volumes overlap with the Turbo Carrera manual and add later revisions, including hydraulic-clutch material and later wiring diagrams. Their model, market, and revision headings distinguish the applicable information.

Companion manual required: Porsche describes this material as a supplement to the regular 911 Repair Manual, which is needed for operations shared with standard 911 models.

PDF Search and Wiring Diagram Readability

Text search and diagram detail: Engine, Transmission, Chassis, and Body/Heating contain searchable OCR text, with gaps in illustrations and some pages. Text search is unavailable in the 407-page Turbo Carrera manual and the Electrics file. None of the six PDFs has embedded bookmarks. Small wiring labels require zooming; some labels in Electrics remain faint or pixelated when enlarged.

The ZIP contains six printable PDFs totaling 973 pages, including covers, forewords, indexes, supplement registers, section dividers, and eight blank pages.

Turbo Systems, Drivetrain Repair, and Chassis Work

The following selected content highlights outline the main workshop coverage rather than reproduce the full contents. Further topics include electronic speedometer sensor testing and rear-fender decal installation.

• Engine service: Engine/transmission-unit removal, separation and reinstallation, piston and cylinder measurement, flywheel service, and valve-spring inspection.

• Turbocharger: KKK turbocharger removal and inspection, shaft-play checks, wastegate and bypass-valve service, boost-pressure testing, oil-supply and oil-pump work, and charge-air cooler removal.

• Fuel and ignition: CIS/K-Jetronic pressure diagnosis, mixture-control unit service, air-flow sensor-plate adjustment, Lambda checks, and Bosch CDI troubleshooting.

• Transmission and differential: Clutch removal and assembly, four-speed case and gearset teardown, selector-fork adjustment, synchronization checks, and limited-slip differential service.

• Chassis and brakes: Front- and rear-axle teardown, wheel-bearing adjustment, axle alignment, Turbo brake and caliper repair, and steering-gear assembly.

• Body and heating: Floor/frame control dimensions, rear axle-tube work, engine-lid service, and automatic heating-control diagnosis.

• Electrical diagrams: Turbo current-flow diagrams for Models 76–78 and multi-sheet wiring diagrams for Models 86–89, supported by accessory circuits and selected Carrera sheets.

Porsche identifies shop foremen and mechanics as users of this repair information; the component-level procedures, dedicated gauges, and test-equipment requirements suit experienced technicians with an equipped workshop.

Engine Types and Market-Specific Diagnosis

The Turbo 3.0 data distinguishes engine types 930/50, 930/51, 930/52, 930/53, and 930/54. Turbo 3.3 material covers 930/60, 930/61, 930/62, 930/63, 930/64, 930/65, 930/66, and 930/68.

Separate CIS and ignition specifications address Europe, the USA, California, Japan, Sweden, and Canada. These distinctions matter when selecting control-pressure tests, idle and CO data, ignition curves, exhaust layouts, and emission-control procedures.

Engine reference material includes piston size and weight classes, crankshaft dimensions, valve-clearance specifications, and camshaft-timing data. Cold- and warm-control-pressure tests address starting and warm-up complaints, while the Bosch CDI troubleshooting charts separate ignition faults from fuel-system and mechanical problems.

Four-Speed Repair and G50/50 Coverage

Four-speed information separates transmissions 930/30, 930/32, 930/33, and 930/34, including the non-US 930/32 and changes introduced for 1977 and 1978. Step-by-step procedures cover transmission disassembly and reassembly, drive-pinion and ring-gear setup, and backlash measurement.

A replacement-parts chart identifies which final-drive components require the pinion, ring gear, or both to be readjusted. This supports repair planning before the measuring equipment and shims are selected.

The Model 89 material identifies the G50/50 five-speed and covers engine removal with the hydraulic clutch, along with clutch-release mechanism assembly details. Porsche refers G50/50 maintenance to the separate Carrera Workshop Manual.

Chassis Changes and Factory Tools

Brake information distinguishes the revised disc/hub arrangement introduced for the 1981 model year and the grease-cap change from chassis No. 93 Z BS 000094.

Fuel-pressure testing references gauge P 378 and adapter P 9114. Boost testing uses tester 9103, with adapter 9103/1 for Turbo 3.3.

Clutch tooling includes 9102 and P 201 a; rear-suspension work references P 289 and P 297 a. Body-checking references include gauges P 683 a/P 863 and straightening attachment set ENS 77.303.

The manual warns that the P 289 holder must be adapted to later rear-axle configurations because an unchanged holder can damage the light-alloy trailing arms. Its CIS cautions also identify the risk of severe mixture-control unit damage if the adjusting wrench remains inserted while the engine is accelerated.

Wiring, Drawings, and Workshop Reference Data

Illustrations include the Turbocharger Oil Supply drawing, engine-type-specific Exhaust System Layout views, Europe/USA/Japan/California hose-connection plans, and the Floor/Frame Assembly Drawing.

Electrical accessory circuits cover automatic heat, air conditioning, power windows, the rear wiper, headlight washers, fog lights, engine-compartment lighting, and the alarm system. The Electrics volume also contains Model 85 alarm diagrams. Later pages mix Carrera and Turbo sheets, so the vehicle and model-year headings remain important when tracing circuits.

Reference sections provide component-specific torque tables, adjustment and wear limits, fuel- and boost-pressure specifications, ignition and CIS settings, wheel-alignment values, brake test data, lubricant and capacity information, and electrical test values.

Fuel, CDI ignition, brake-hydraulic, and refrigerant-system work should be carried out only with the correct workshop equipment and the factory safety precautions in place.

Sample Turbocharger Shaft-Play Limits

The turbocharger inspection section specifies maximum shaft end play of 0.35 mm. Its separate radial-play check specifies a maximum of 0.65 mm, measured at the turbine end.