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Oil overpressure

Re: '87 5K CSTQ, 240K miles

     Due to my travel schedule I've just now gotten the head off the engine.
The exhaust valves severely impacted the tops of the pistons - all five.  The
intakes valves did not.  In theory the intake valves had the same opportunity
to touch the pistons on the opposing side, but they chose not to.  The
cylinders have only a small wear detectable at the top of them.  The two with
the pistons on the down-stroke still show some of the original honing marks.
The cross-hatch is quite distinct.  I was impressed.
     ITEM ONE - 
     I intend to have the head reworked.  Been checking with Bob at Shine
Racing Service.  At the moment I am not planning to have the head ported, just
gasket matched - unless it is the concensus of several Q-listers that porting
is necessary.  My thought is that the porting would probably move the power UP
the rpm band, and there is not enough low end now.  Comments welcome (or if
you remember where you made the comments before send me a date and I'll check
the archives).
     ITEM TWO - 
     Due to the impact marks on the pistons, I do not feel comfortable reusing
them as-is.  I am afraid there would be "hot spots" possible, even if they
were polished out.  I have two spare '85 turbo engines that can donate
pistons.  I am assuming I should change rods and pistons at the same time.
I'd like to keep the same rods, but don't know how reasonable that is.  Again
comments welcome.
     ITEM THREE - 
     Since the wear is so small I am thinking about simply re-honing the
cylinders and using news rings.  Will that work?
     ITEM FOUR -
     Someone recently listed a two piece manifold for sale.  Is it still
available?  If so, please e-mail a price.
     ITEM FIVE -
     With the mileage on the car I probably should have the turbo replaced or
rebuilt.  What is the thought here?  Find a low mileage water cooled turbo?
Or have this one rebuilt?  Any recommendations on a rebuilder?  Would a turbo
from a 20v car help bottom end on a 10v engine?
     (I already copied all the notes regarding turbo theory, so I am not
trying to restart that thread.  Just asking recommendations based on BTDT so I
can make a decision.)

     As always, your help and insight appreciated.

     A Little Less Confused in Bucksnort.