Valves & spark plugs don't mix!

[Ralph Moorhouse <ralfalfa@domain.elided>]

A friend has a '80 Spider in which the plugs in cylinders 2, 3, & 4 have 
made contact with the side electode of the spark plugs.  As best I can tell 
from looking into cylinders with my little probe light, I see no evidence 
of valves & pistons having made contact.  What might have caused 
this?  Needless to say it doesn't run too well with zero gap on the plugs!

tnx
Ralph
Houston, TX

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