1125 PISTONS TECHNICAL DATA (M850i coupe/convertible/Gran Coupe xDrive sedan)
1125 TECHNICAL DATA OVERVIEW
| Permissible total wear tolerance between piston and cylinder (engine operated) | ||
| Piston installation clearance (piston worn) | 0.25 mm | |
| Piston diameter | ||
| Measure the piston diameter at distance (A) from the lower end of the piston skirt. | Distance (A) to the lower end of the piston skirt | 18 mm |
| Nominal dimension of piston diameter | 88.987 +0.02-0.02 mm | |
| Piston installation clearance (piston new) | ||
| Piston installation clearance (piston new) | 0.003... 0.023 mm | |
| Piston ring 1st groove A | ||
| Side clearance. | 0.02... 0.07 mm | |
| Piston ring 1st groove H | ||
| Annular groove height. | 1.21... 1.24 mm | |
| Piston ring 1st groove S | ||
| End clearance. | 0.15... 0.30 mm | |
| Piston ring 2nd groove A | ||
| Side clearance. | 0.015... 0.06 mm | |
| Piston ring 2nd groove H | ||
| Annular groove height. | 1.51... 1.53 mm | |
| Piston ring 2nd groove S | ||
| End clearance. | 0.30... 0.50 mm | |
| Piston ring 3. Groove-A DSF ring | ||
| Side clearance without spiral expander. | 0.02... 0.06 mm | |
| Piston ring 3. Groove-A U-flex ring | ||
| Side clearance without spiral expander. | 0.02... 0.08 mm | |
| Piston ring 3rd groove H | ||
| Annular groove height. | 2.01... 2.03 mm | |