Safe Installation Tip: Replace VR6 Valves One at a Time

Because the Audi Q7 3.6L VR6 (BHK) cylinder head uses both short and long valves, one of the safest installation methods is to replace valves individually instead of removing all valves at once. 

Recommended Procedure:

1. Remove one original valve only.
2. Compare the old valve with the replacement valve:
   • Overall length
   • Valve head diameter
   • Stem diameter
   • OEM reference number
3. Install the matching replacement valve into the same position.
4. Continue cylinder by cylinder until all valves are replaced.

Please check the details for 24pcs X VR6 BHK BUD CDVD Inlet/Outlet Valves Set

This simple method helps prevent one of the most common mistakes during VR6 cylinder head rebuilding:

Installing a long valve into a short valve position or a short valve into a long valve position. 

Why Is This Method Safer?

The VR6 valve arrangement can be confusing because the cylinder head contains multiple valve lengths that may look almost identical when mixed together.

Once all original valves are removed and placed on a workbench, it becomes easy to lose track of:

• Cylinder position
• Intake vs exhaust location
• Short vs long valve position

A single misplaced valve can affect:

• Valve train geometry
• Valve spring installed height
• Cam follower preload
• Valve lift
• Piston-to-valve clearance

Professional Engine Builder Tip

For a complete cylinder head rebuild, professional workshops usually mark every valve location before removal.

A simple organization method:

Use:

• Valve trays
• Numbered containers
• Magnetic organizers

to keep every component in its original position.

Important Note

Even when replacing valves one-by-one, always perform final measurements:

✔ Valve stem-to-guide clearance
✔ Valve seat contact width
✔ Valve face sealing
✔ Installed spring height

A new valve is not only about matching the length — it must also correctly seal with the cylinder head.