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The G161Z is the Petrol 1.6L 4 Cylinder engine found in the [[Terminology|RWD]] Gemini series from the [[TX Gemini|TX]] to the [[TG Gemini|TG]].<br>

==General Description==
The Model G161Z engine is a watercooled 4-cycle 4 cylinder in-line overhead camshaft type gasoline engine.<br>
The cylinder head is die cast with alluminium alloy and is bolted to the cylinder block via the wire-woven gasket which has excellent durability. The combustion chambers are of dome type design with the "V" type valva arrangement with the spark plug at the centre.<br>
The intake and exhaust ports are of the cross-flow design to ensure intake and exhaust efficiency. The camshaft is supported by 5 bearings, the caps of which are integrated with the rocker arm shaft brackets which, in turn, are bolted to the cylinder head. The cylinder block is cast integrally and water jacket is arranged symmetrically with the cylinders for efficient cooling of the cylinders. The engine adopts centre-mounting method with the mounting on the centre part of the cylinder block.<br>

The crankshaft is forged integrally with balance weights and is rigidly supported with 5 bearings. The pistons are solid type made up with Low-EX alloy which is low i rate of thermal expansion. The 1st and 2nd compression rings are taper-face type and oil control are of a combined type consisting of 3 piece rings. The connecting rods are in the shape of the letter "I" in cross-section and are semi-floatingly assembled to the piston with the piston pin press-fitted to the connecting-rod small end. The valve mechanism is a single over head cam type utilizing a double rocker arm system in which the intake and exhaust valves are operated independently. The rocker arms are operated directly by the camshaft which in turn is driven by the chain. The timing chain is automatically adjusted by the means of a tensioner with a mechanical adjuster which is installed on the driven side. The valve system adopts double action type inner and outer springs to improve follow abilty of the valves at high speeds.<br>

The front cober which is die-cast with aluminium houses the water pump, oil pump, oil filter and distributer. The engine lubrication system is full-flow filter pressure circulation type incorporating a trochoid type oil pump and a cartridge type oil filter.<br>
The cooling system is pressure circulation type and includes an impeller type water pump and wax pellet type thermostat with jiggle valve. The fuel system includes a Stromberg diaphragm type two barrel carburetor incorporating an electrical automatic choke device. The fuel pump is a centrifugal electric type and is installed within the fuel tank. The fuel system adopts a fuel return method in which excess fuel is automatically returned to the fuel tank through the pipe line.<br>
The electrical system is designed to operate on 12v power supply and utilizes negative ground polarity. The electrical system included large capacity generator, starter motor and battery. Exhaust gas control system consists of a blow by gas control system (PVC), evaporative emission control system (EEC), coasting richer system (CRS), intake air control system (CCS), idle limiter, running-on soleniod, inresistance, lean-set on carburettor, distributor with maximum advance angle control system, etc

==Engine Specifications==
CODE = G161Z<br>
COMPRESSION RATIO - TX/TC/TD = 8.7:1<br>
COMPRESSION RATIO - TE/TF/TG = 8.3:1<br>
BORE = 82.00mm<br>
STROKE = 75.00mm<br>
CAPACITY = 1584cc (96.66ci)<br>
POWER - TX Pre ADR27A = 63kw / TX Post ADR27A = 61kw / TC&TD = 61kw / TE-TG = 50kw<br>
TORQUE = 119nm (88lb/ft) @ 3400rpm<br>
COMPRESSION PRESSURE = Minimum 125psi (861kpa)<br>
IDLE SPEED = 700rpm<br>
IGNITION TIMING = 6 deg btdc set at idle speed<br>
DISTRIBUTOR DWELL ANGLE = 50 - 54 deg<br>
FIRING ORDER = 1-3-4-2 ***Gemini distributor spins anti-clockwise***<br>
SPARK PLUGS = NGK BP6ES (NGK BP5ES for tired smokey engines)<br>
SPARK PLUG GAPS = 0.7mm - 0.8mm<br>
VALVE CLEARANCES = Cold: Inlet = 0.15mm / Exhaust = 0.25mm<br>
VALVE CLEARANCES = Hot: Inlet = 0.20mm / Exhaust = 0.30mm<br>
OIL PRESSURE = 7psi (49kpa) at idle<br>
OIL PRESSURE = 47-71psi (390-490kpa) at 2800rpm<br>
SUMP CAPACITY = 3.2 litres without filter<br>
SUMP CAPACITY = 3.6 litres with filter<br>

==Cam Shaft Specifications==
Inlet Valve:<br>
opens (B.T.D.C) 21 deg<br>
closes (A.B.D.C) 65 deg<br>
duration 266 deg<br>
<br>
Exhaust Valve:<br>
opens (B.B.D.C) 55 deg<br>
closes (A.T.D.C) 20 deg<br>
duration 255 deg<br>