For a camshaft marked "84" the following figures apply:
inlet valve opens (BTDC) 10°
inlet valve closes (ABDC) 58°
exhaust valve opens (BBDC) 51°
exhaust valve closes (ATDC) 23°
With reference to the pistons, I am assuming you are referring to the same M127.981 engine.
If so, the the following sizes are applicable (with reference to piston sizes):
Standard = 82.00 mm
Intermediate repair = 82.25 mm
1st repair = 82.50 mm
2nd repair = 83.00 mm