Vibration in front of 4KCSQ

[Nicholas Menaker <72074.2716@CompuServe.COM>]

I have developed a bit of vibration in the front end of my quattro.  Just
put some new TSW evo wheels with D40/M2 dunlop 205/55/15 tires on.  I
noticed a little bit of vibration, but not TOO noticeable, until I finished
the suspension upgrade.  Boge turbo gas and Eibach Pro kit shocks all
around.  Now, at about 58-70 miles per hour( on the speedo, probably out of
adjustment due to the tire upgrade) there appears a rather pronounced
vibration that shakes the wheel a bit, and brings a vibration to the front
end.  After about 75 miles per hour, the vibration is gone.  I know what
some of you are saying, "Just don't drive less than 75 mph, but sometimes
current road conditions... 

Anyway, I have had the wheels checked, and they seem perfect. (I should
hope so, they are brand new) The tires could be just a little bit "unique"
shall we say, but I don't think it should be that much to create this
vibration. I have had the tires checked and rebalanced already once.  Could
this be a wheel bearing?  They SEEM fine, no play.  What about CV joints? 
I did noticed some CV grease on the inside of the wheel surface and pulled
the wheel and checked the boot.  It had been put on a little loose, and
needed refitting, but could th CV have been damaged?  How does one check
this?
Someone wrote about a rattle in the front end, going over uneven bumps and
things.  They tracked the rattle down to shock tower top bolts not being on
tight enough.  Could this have some effect?  How does one check this?  What
should it be torqued to.?  Could the larger tires and wheels have some
effect on the vibration?  Is the increased weight, I am guessing that the
TSW Evos are heavier than the stock four bolt wheels?  And the Dunlops are
bigger and I am sure steel belted.  Could this CREATE vibration? 

I appreaciate all the responses
Nick out

'87 4KCSQ  145K,