>In addition to possibly dropping crud into the cylinder, some people believe
>that re-tapping will weaken the threads (basically by converting them from
>rolled 85% threads to cut 100% threads).
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For what it's worth . . .
These people would be mistaken as these threads would have been cut with a
tap. Rolled threads are primarily reserved for bolts and screws which can
be turned on a machine. It would be very difficult to roll threads of this
type on a large stationary block of material and every thing I have seen
with regards to original manufacturing engine machining uses a single
operation, with multiple taps/drills to do these operations in a single
step for production quantities -
Barry Schwartz (San Diego) bschwart@pacbell.net
72 PI, V6 Spitfire (daily driver)
70 GT6+ (when I don't drive the Spit)
70 Spitfire (long term project)
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