Help diagnosing metallic scraping noise

[Steven Papatrefon]

I finally finished my high compression motor swap and got it ready for its
first test drive.  Started to drive out of the garage and I hear a metallic
scraping noise coming from the front wheels, mostly the passenger.  It is
speed dependent and doesn't start or stop by applying the brakes.

Pulled it back into the shop, put it on the lift and took the wheels off.  The
rotor near the top had a very small groove cut into it.  I removed the caliper
and looked for a stone or something that could have done this.  Didn't see
anything.  I felt the surface of the break pad and it was smooth.  I used
brake cleaner on the pads and rotor and bolted it all back up.  Took it for
another test drive and the same noise.

Brought it back into the shop, took the wheels off again, started the motor
and put it into first gear.  I could not hear any scraping noises!  It appears
that the problem occurs when the wheels are weighted.

I talked on the phone to a mechanic friend.  He said, among other things, that
if the large axle nut was not torqued enough there could be some play which
could cause this noise.  I don't know if that would be the bearing or the
actual axle making the noise.  I'm gonna have our mechanic at work take a look
at it tomorrow.  Any input would be appreciated though.  Keep in mind that
before the wheels, calipers, rotors and axles were taken off as part of my
engine swap, I had absolutely none of these problems so something happened
when these things were reinstalled.

Steve