TQC Breaking up

[cngnyec@nyc.pipeline.com (Richard Davis)]

    I am soliciting any and all ideas in an effort to keep my remaining
hair in my head! 
   Just finished buttoning up my 81 TQC from fresh pistons, rings gaskets
et al.  I am experiencing intermittant losses of power that don't SEEM to
be RPM or boost specific.  It is very hit or miss.  sometimes in any gear I
can rev straight towards redline no problems, other times it will loose
power usually between 3200 and 4k. (this is with boost pressures set less
than 10 PSI.  The injectors are all clean and flow properly, upstream fuel
delivery system seems OK.  Cap rotor and distributer all check out.   I
have double checked all previously disconnected wires and grounds and can't
seem to find any discontinuities.  Caveat this did not happen before I took
it all apart and I don't seem to have any extra pieces!  (since I didn't
think it needed new pistons until I got into it, the Audi deities have been
sacrificed to!) 
  Ideas, like experiences or explosives? 
Mike