The cylinder head bolt is the metal element that connects the head to the cylinder blocks; the cylinder head gasket and the cylinder block itself. Correct tightening of the cylinder head bolt is a critical factor for the normal operation of the engine oil channels, coolant and combustion chamber, since excessive or insufficient tightening leads to incorrect contact sealing pressure, which will affect the failure of the power unit (cracks), because the cylinder head is part of the combustion chamber.

1. COUPE (89, 8B)
2. 100 (4A2, C4)
3. 100 Saloon (4A2, C4)
4. 500 (4A2, C4)
5. 80 (8C2, B4)
6. 80 Saloon (8C2, B4)
7. 90 (8C2, B4)
8. 80 Avant (8C5, B4)
9. 100 Avant (4A5, C4)
10. CABRIOLET (8G7, B4)
11. A8 (4D2, 4D8)
12. A8 Saloon (4D2, 4D8)
13. A8 / S8 (4D2, 4D8)
14. A4 (8D2, B5)
15. A4 Saloon (8D2, B5)
16. A4 / S4 (8D2, B5)
17. A6 (4A2, C4)
18. A6 Saloon (4A2, C4)
19. A6 / S6 (4A2, C4)
20. A6 Avant (4A5, C4)
21. See more in applications

The construction of the cylinder head bolts

The FEBI BILSTEIN brand Cylinder Head Bolt consists of a single piece of metal, which has been shaped into a bolt. It happens with a low-lying thread and a thread starting approximately from the center of the product (depending on the types of cylinder blocks).

To solve the problem of correct sealing, two types of cylinder head bolts have been developed - with a rolled bar and tension bolts. The tension bolt has a flow rate and deforms plastically, which guarantees a uniform tightening compared to a conventional cylinder head bolt. The stretch bot does not need a lift, as it can move at a certain angle by itself when correctly twisted.