11 12 Cylinder Head
N55 ENGINE (UP TO MODEL YEAR 2018):
11 12 CYLINDER HEAD WITH LID - N55 TECHNICAL DATA SPECIFICATION
| Cylinder head height: Original dimension | mm | 112.00 ± 0.05 |
| Machining limit | mm | 111.70 ± 0.05 |
| Valve guides are not available as replacement parts. | ||
| Inner diameter of installed valve guide | ||
| Original intake valve | mm | 5.00... 5.02 |
| Original exhaust valve | mm | 6.00... 6.02 |
| Tilt clearance, maximum (wear between valve and valve guide) | mm | cannot be measured |
| Bearing of camshaft | ||
| Guide bearing (width) | mm | 22.00... 22.05 |
11 12 CYLINDER HEAD WITH VALVE SEAT COVER - N55 TECHNICAL DATA SPECIFICATION
| Valve seat angle | ° | 45 |
| Correction angle: outer | ° | 35 |
| Correction angle: Inner, exhaust valve | ° | 60 |
| Correction angle: Inner, intake valve | ° | 65 |
| Valve seat width: Intake | mm | 1.25 +0.2 |
| Valve seat width: Exhaust | mm | 1.65+0.2 |
| Ø theoretical valve seat | ||
| Valve seat surface: Outside dia. inlet | mm | 30.4+0.1 |
| Valve seat surface: Outside dia. exhaust | mm | 26.6+0.1 |
11 12 TECHNICAL DATA OVERVIEW
| Cross deviation from flatness | |
| max. 0.05 mm | |
| Longitudinal deviation from flatness | |
| max. 0.10 mm |
S55 ENGINE (AS OF MODEL YEAR 2019):
11 12 CYLINDER HEAD WITH LID - S55 TECHNICAL DATA SPECIFICATION
| Cylinder head height: Original dimension | mm | 112.00 ± 0.05 |
| Machining limit | mm | 111.70 ± 0.05 |
| Valve guides are not available as replacement parts. | ||
| Inner diameter of installed valve guide | ||
| Original intake valve | mm | 5.00... 5.02 |
| Original exhaust valve | mm | 6.00... 6.02 |
| Tilt clearance, maximum (wear between valve and valve guide) | mm | cannot be measured |
| Bearing of camshaft | ||
| Guide bearing (width) | mm | 22.00... 22.05 |
11 12 CYLINDER HEAD WITH VALVE SEAT COVER - S55 TECHNICAL DATA SPECIFICATION
| Valve seat angle | ° | 45 |
| Correction angle: outer | ° | 35 |
| Correction angle: Inner, exhaust valve | ° | 60 |
| Correction angle: Inner, intake valve | ° | 65 |
| Valve seat width: Intake | mm | 1.5 +0.2 |
| Valve seat width: Exhaust | mm | 1.65+0.2 |
| Ø theoretical valve seat | ||
| Valve seat surface: Outside dia. inlet | mm | 30.4+0.1 |
| Valve seat surface: Outside dia. exhaust | mm | 26.6+0.1 |
11 12 TECHNICAL DATA OVERVIEW
| Cross deviation from flatness | |
| max. 0.05 mm | |
| Longitudinal deviation from flatness | |
| max. 0.10 mm |