> > Paul,
 > >
 > >   Cant remember if this was asked previously or not. How do
you account for
 > > the fact that with the most common PSRUs the prop turns
backward relative
 > > to a Lyc? I'm sure most kit manufacturers add thrust offset to
their mounts
 > > (Vans does) so the new front housing will need to offset the
opposite way
 > > to take this back out. Vans mounts also displace the mount
points sideways
 > > to correct for the offset angle so that the prop hub is on the
centerline
 > > of the airplane. The new housing would have to account for this as well.

 >Tracy says he does not notice it.

 > >   Do all kitplane manufacturers use similar schemes with the same offset
 > > angles? If not, then your new front cover isnt going to be as
universal as
 > > you'd like it to be. But if this were possible, sign me up. I think it
 > > would be a great leap forward.
 > >
 > >   I'll turn the cost issue back to you. What do you think such a cover
 > > would have to sell for? I think the market would be pretty
large. I have 2
 > > friends right now who would be putting 13Bs on their airplanes but are
 > > intimidated by the prospect of having to build a mount.
 > >
 > >   I do agree with Charlie though, in saying that I think it
would probably
 > > be better if it were a conical style rather than a Dynafocal style. If
 > > nothing else, conical rubber isolators are a fraction of the cost of
 > > Dynafocals. I think most kit plane manufacturers offer both
types of mounts
 > > to their builders.
 > >
 > > Mike Wills

 Paul,

   Tracy built a mount with no offset (as did I based on Tracy's input).
 Which is not the same as what your talking about. The stock mount for my RV
 has offset going the wrong way for the Mazda/RD1 combo. I cant imagine that
 this wouldnt be noticeable so have to believe that the new front housing
 would at the least need to compensate to get everything back to a zero
 thrust angle.

 > Mike Wills

This would be no problem at all if Tracy went to the 2.85:1 PSRU.
Prop rotates in right direction.

Paul Lamar

Tailwind engine mounts have no offset in theory.  In fact, most of
them are built in space without a fixture of any kind and you can
imagine that many of them must warped out of alignment, one way or
the other. Difficult to see once the engine is installed.   Yet first
flight reports usually say that the airplane flies normally.   I
personally have flown in three TWs that had motor mounts built
without a fixture and all three felt about the same to me and had no
trim issues.  Also, it is quite possible to kick an engine mount one
way or the other with spacers at the firewall . I saw a Cassutt racer
with 3/4" spacers on one side, none on the other.  Apparently helped
turning left.   The Tailwind does off set the leading edge of the
vert. stab 1/2".  I moved this to the opposite side for the rotary.
Jerry

 
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