Thread: Kissed pistons
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les_garten les_garten is offline
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Join Date: Jun 2003
Location: PSL, FL
Posts: 861
Angry Kissed pistons

Hello,
I rebuilt my 1985 930. During the process I changed the cams to SC cams and kept the same Stock Pistons and Cylinders and re-ringed them. During the break in process I had a sudden stoppage of the car with poor running afterwards.
I pulled down the motor and found four kissed pistons. There is a strange pattern to the imprints on the pistons. The right and left side of the motor have mirrored damage patterns.
Pistons 2 and 5 have exactly the same impact mark as you can see on # 2 in the picture. Pistons 3 and 6 have identical marks and the are shallower than the marks on 2 and five, but as I said, the marks on 3 and 6 are identical are also.
Pistons 1 and 4 are untouched. The only valves affected are these 4 exhaust valves. To be perfectly honest I don't fully understand the valve timing on Porsche's and feel that I screwed up the valve timing.

My questioin is: Has anyone seen this pattern before.
Old 03-26-2005, 08:23 AM
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