<VV> Media Blast for Engine Clean-up

[edward szuch]

What are your suggestions for a blast material to clean up a cylinder head?
 1 Outside surfaces, 2 Combustion chambers, 3 Valve and rocker area.  I
plan to do a general wash and parts cleaner scrub first but then want to
get the carbon and varnish off the chamber and rocker areas.  Glass beads
seem to do a great job for appearance but I'm concerned about getting the
beads embedded in the aluminum and then releasing back into the engine oil
after the engine heat cycles.  Any words of wisdom?
Thank you.
Gary Szuch