911 - 964 - 993 - Turbo - RS - Cup cylinder head revisions Porsche.
An AMS cylinder head revision includes the following work:
- Check cylinder head for cracks
- Clean the cylinder head pore-deep using the shoot peening process and compact the surface
- Press out damaged intake and exhaust valves, drill them out if necessary
- Re-drill and fine-hone the valve guide bore
- Turn oversize valve guides to overhang dimension
- Heat the cylinder head in a convection oven
- Press the dry ice cooled valve guides under high pressure
- Valve guides at 90° to the valve plate - honing and fine-honing the contact surface
- Milling or fine turning the cylinder head flat surface.
- Milling existing valve seat rings at 3 angles with 3 different steps
- Compress valves using the shoot peening process on the plates
- Regrind valves in 3 stages on the valve plates
- Re-grind valves onto the valve seat(s)
- Measure and adjust the immersion depth of the valves
- Valve stem - Install seals on the valve guides and valves
- Check valve springs and adjust and install with required preload
- Install valve cones to fix the valve plates to the valves
