>
          > 3) The VAM muffler *almost* fit.  The exhaust pipe hits one of
         the mount
          >
          > tubes, preventing the exhaust manifold flange from seating
         against the
          >
          > engine correctly.  There seem to be 3 possible solutions:
          >
          >    A) Make an insert for the manifold flange which adds appx
         1/4".  Not
          >
          > convinced the bolts are long enough for this.
          >
          >    B) Cut the exhaust manifold pipes & lengthen them so the VAM
         moves
          >
          > 1/4" - 3/8" farther away.
          >
          >    C) Cut the VAM exhaust tube & increase the angle toward
    aft so it
          >
          > clears tube.
          >
          >
         Mark,   When I built the muffler, I did it with the engine mount in
         place.  I had it off and on many times.  It had to be angled
    just so to
         slip it over the flange studs, but it did fit. I have no ideal
    why it
         would not fit now.  Of your proposed solutions, the last one
    would be
         easy to do. Cut through three sides of the exhaust so the last
    side can
         act as a hinge. (It can be cut on a band saw or with a plasma) Heat
         with a torch and pull it the position  you want.  I can send
    you some
         321 strips for the patch and also some 347 tig rod (required to
    weld
         321).   Or, you can patch it with 304, readily available
    everywhere.  To
         weld 304 to 321, use 309 rod.

           I am very disappointed that you are having difficulties,

           Jerry


    We were able to get the muffler over the studs no problem.  The trouble
    was getting it to fit completely against the engine - in this case, the
    bottom could not touch because the exhaust pipe was contacting the
    engine mount.  How thick is the gasket material which fits between the
    engine & the muffler flange, Jerry?  We were doing a dry-fit, but it
    didn't seem that close to fitting -- perhaps you had gasketing in there
    & it was enough?

    Agree that increasing the angle of the exhaust square-tube is the
    easiest way to adjust it.  Do you suppose there is any reason to make
    this adjustment way up by the VAM, or could it be done a couple of
    inches down (where it will be easier to do)?  The only difference is
    that doing it a couple of inches down would put a 'bend' in the pipe --
    can't see that a bend would make any difference.

    Mark & Mark

    It was kind of loud on the dyno so a bend might help.
    Also you might want to weld in a few of these while you are
    at it. They are reputed to reduce the noise.

    BTW Mark if you use the stock M2 cowl what are you going to
    do with the cheeks?

    Paul Lamar



We're not going to use the stock cowl.  We were mostly curious to see
what would happen & the cowl was sitting there... so we helped
ourselves...  A few measurements & lots of pictures later, we quietly
returned it to the hangar from which we'd borrowed it.

Is the idea that the exhaust louvers reflect sound waves back up the
pipe, thus deadening it somewhat?  It looks like the louvers are bent in
v-shapes with the points pointing down -- again to reflect sound up?

You've mentioned several times that the VAM didn't seem to be reducing
exhaust noise as much as had been hoped.  I assume you were inside when
on the dyno -- thus getting reflected noise from the walls.  I guess I
am hoping it will perform better 'in the field' than it did in the lab..

Mark & Mark

Interesting. I just overlayed the layout on a scale drawing
I had of the M2. Looks like there is plenty of room in there.


Paul Lamar


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