Head Disassembly

Prior to rebuilding...

...After rebuild

The last part of taking the engine apart is complete head disassembly. Using a large C-Clamp style valve spring compressor the valve keepers can be removed and the entire valve assembly can be taken apart.

Several exhaust valve stems were measured. Gage blocks were set up for the minimum wear diameter of the valve stem. An outside micrometer was then fixed to the gaged dimension. All of the valve stems measred were fairly consistent in their wear pattern. At the top and bottom of the stem the wear was below the usable dimnesion stated in the spec book from Porsche. The middle of the valve stem was well within the wear limit. This is a typical wear pattern for valves and these were not reusable.

All six heads were taken to Extreme Cylinder Head in Palm City, Florida, to be completely reworked. The cylinder sealing surface needed some serious cleanup and .010" was removed. A larger cylinder base gasket must be used to make up the removed material or there will be issues with the timing chains and cam binding.

Tear Down Part: 1 2 3 4 5 6