Engine Design
| Designation | 987 | 987 S | Cayman S |
|---|---|---|---|
| Type | 6-cylinder aluminum opposed-cylinder engine, water-cooled | ||
| Crankcase | Vertically split light alloy cylinder housing with separate aluminum crankshaft bearing housing with GGG inserts | ||
| Crankshaft | Forged, supported by 7 bearings | ||
| Crankshaft bearings | Three-component plain bearings | Ø 63, sub-groove, three-component plain bearings | |
| Connecting rods | Forged Crack connecting rod | ||
| Con-rod bearings | Three-component plain bearings | ||
| Pistons | Light alloy cast | Pressed light alloy | |
| Cylinders | Lokasil oil running surface | ||
| Cylinder head | Three-part light alloy head | ||
| Valve guide | Bearing material pressed in | ||
| Valve arrangement | Two input and output valves per cylinder suspended in parallel v-format | ||
| Diameter of inlet valve | 33.3 mm | 37.1 mm | 40.2 mm |
| Diameter of exhaust valve | 28.1 mm | 32.5 mm | 34.5 mm |
| Valve lift of inlet | 9.85 mm | 10.5 mm | Large 11 mm Small 3.6 mm |
| Valve lift of outlet | 9.85 mm | 10 mm | 11 mm |
| Valve gear | Via flat-base tappets | Switchable flat-base tappets | |
| Camshaft | Chilled cast iron, hollow-cast | ||
| Camshaft adjustment | Porsche VarioCam with axial camshaft adjustment | Porsche VarioCam Plus with axial camshaft adjustment and valve lift control | |
| Camshaft drive | From the crankshaft via a 3/8" tooth-type chain to the intermediate shaft, and from there to the inlet and exhaust camshafts via one 3/8" duplex roller-type chain each. | ||
| Valve clearance | Hydraulic valve clearance compensation | ||
| Timing: intake opens, early/late | 21° before TDC/19° after TDC | 26° before TDC/14° after TDC | Large lift 29° before TDC/11° after TDC |
| Timing: intake closes, early/late | 9° after BDC/49° after BDC | 20° after BDC/60° after BDC | Large lift 20° after BDC/60° after BDC |
| Timing: intake opens, small lift, early/late | - | - | 1° before TDC/39° after TDC |
| Timing: intake closes, small lift, early/late | - | - | 59° before BDC/19° before BDC |
| Timing: Outlet opens | 39° before BDC | 39° before BDC | 50° before BDC |
| Timing: Outlet closes | 8° before TDC | 6° before TDC | 4.5° after top dead center |