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

• 973 PDF pages across six files: Engine, 177 pages; Transmission, 99; Chassis, 74; Body/Heating, 31; Electrics, 185; and the Edition 1976 base manual, 407. The base volume is identified as US Order No. WKD 481 321, Print No. 48 13.21.
• Covers Model 75 data through Model 89 updates, including 3.0-liter and 3.3-liter 911 Turbos, regional engine/emissions configurations, four-speed Type 930 gearboxes, and the Model 89 G50/50 five-speed with hydraulic clutch.
• Engine repair material includes engine removal, piston and cylinder inspection, flywheel machining data, camshaft timing, chain-tensioner service, valve adjustment, dry-sump lubrication, and Turbo oil-pump work.
• Turbocharging and CIS/K-Jetronic sections document turbocharger and wastegate service, charge-pressure testing, intercooler removal, fuel-pressure diagnosis, mixture-control work, Lambda checks, ignition troubleshooting, and emissions-system repair.
• Chassis and body coverage includes axle removal, wheel-bearing adjustment, alignment, brake and caliper repair, steering overhaul, Turbo body reference dimensions, straightening fixtures, engine-lid work, and automatic-heater diagnosis.
• Electrical support ranges from early Turbo USA current-flow diagrams to Model 89 multi-sheet wiring diagrams, with system legends, fuse assignments, component and plug locations, ground points, relay layouts, and year-specific accessory circuits.

Factory Service Documentation

This Porsche factory workshop material follows the repair-group numbering used for labor and warranty operations. The Edition 1976 base publication is supplied with five later, system-organized files containing replacement and supplement pages printed through July 1989. The files overlap substantially, so 973 is the total file-page count, not a count of unique pages.

Porsche describes the repair manual as material for shop foremen and mechanics. Its gearbox setup, CIS pressure testing, and body-dimension work assume solid mechanical experience and workshop measuring equipment. The manual covers repair operations that differ from the regular 911; Porsche directs the reader to the separate 911 Repair Manual for all other work and to service-training literature for general design-and-function material.

Engine, Turbo, and Fuel-System Coverage

The technical data separates 3.0-liter engine Types 930/50 through 930/54 from the 3.3-liter 930/60, /61, /62, /63, /64, /65, /66, and /68 versions, including Europe, USA, California, and Japan differences. Engine groups address the light-alloy air-cooled crankcase, crankshaft and flywheel, Nikasil cylinders, piston grading, cylinder heads and valve gear, cooling fan, dry-sump oil circuit, oil coolers, and turbocharger scavenge pump. Factory tables provide torques, machining dimensions, wear limits, clearances, lubrication data, and adjustment specifications.

Turbo and fuel-system diagnosis covers shaft inspection, wastegate function, charge-pressure and safety-switch checks, turbo oil supply, CIS fuel-pump delivery, cold and warm control pressure, full-throttle enrichment, system pressure, pressure-gauge bleeding, air-flow sensor-plate position, fuel-distributor service, idle/CO adjustment, and Lambda testing. Exhaust layouts are separated by engine type, with air injection, reactors, EGR, exhaust-temperature control, and regional hose plans.

Transmission, Chassis, and Body Repair

Four-speed coverage distinguishes transmissions 930/30, 930/32, 930/33, and 930/34. It includes clutch and power-clutch work, shift controls, shafts and gears, selector-fork adjustment, synchronization, differential and limited-slip differential assembly, plus drive-pinion, ring-gear, shim, and backlash setup. For Model 89, the manual identifies the reinforced G50/50 five-speed, documents the hydraulic clutch changes, and refers to the separate Carrera workshop manual for underlying gearbox maintenance information.

The manual warns that the CIS adjustment wrench must be removed before the engine is accelerated, or the mixture-control unit can be severely damaged. It also cautions that the pull-type clutch release bearing must not be loaded toward the driven plate and that a removed pressure plate must not be set down on the bearing.

Turbo-specific body information includes floor/frame checkpoints, repair reference dimensions, P 863/P 863a checking gauges, and the ENS 77.303 straightening-bench attachments. Chassis sections add suspension disassembly, wheel-bearing checks, axle alignment, brake-pad and caliper work, and steering assembly. The manual also covers automatic-heater diagnosis, relay locations, electronic-speedometer testing, center-console removal, and Turbo engine-lid procedures.

Wiring, Diagrams, and Shop Data

Named visual references include the turbocharger drawing, engine-type exhaust layouts, regional hose-connection plans, ignition advance curves, Model 76-78 Turbo USA current-flow diagrams, and Model 86-89 Turbo wiring sheets. Later electrical sets break out K-Jetronic/oxygen-sensor circuits, heating and air conditioning, central locking, instruments, fuse positions, plug connections, and ground points. Accessory diagrams cover power windows, headlight washers, automatic heating, the M 559 air conditioner, and the alarm system.

Referenced factory tools include the P 378 fuel-pressure gauge, P 377/P 229 c mixture tools, 9102 clutch mandrel, P 254 bearing tools, P 375 mandrel, and differential fixtures 9145/9196. Fuel-pressure testing, engine removal, brake repair, and air-conditioning work involve pressurized systems or heavy assemblies; use the specified equipment and normal shop safety practices.