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10V heads

Well, my 10V hydraulic head is finally at the shop where it will get
ported/polished/massaged/etc.  I thought I might throw a couple'a ideas
out there to y'all and maybe get back some advice/experiences.

1) The original (now deceased) ABT head had the stock 33mm exhaust valves, 
but the intake valves were increased from 38mm to 40mm.  The guy at the
head shop claims I'll get better performance if I instead open up the
exhaust.  So, since I have 2mm of extra valve size to play with, do
I put it all on the exhaust side, split the difference and go 1mm up 
in size on both the intake and exhaust, or stick to what I had before 
and increase only the intake by 2mm?

2) The old head had it's intake ports widened a significant amount,
and the openings in the intake manifold were widened to match.  The
problem here is that because of the shape of the intake manifold, it
was only widened as far into the intake runners as the die grinder
could reach.  The guy at the head shop says this is bad, because as
the air comes through the throttle body and enters the runners, it's
gonna expand as it goes from the narrow region to the wider region, 
thus reducing the air velocity before it enters the head.  He claims
I either need to widen the intake manifold runners along their entire
length (extrude honning, perhaps?), or get a stock intake manifold 
and not bother widening the passages on either it or the head.  What
do y'all think?  Anyone out there have any experiences with extrude
                                                    Dan Bocek