Jim,

I got about 900 hours before cracking started.  After the second crack, I braced the pipes to the rear of the engine(see pdf).  Everything moves together as one unit and is much stiffer now.  The pipes are restrained in the plane of the braces which is close to vertical.  They are free to move along their length with little resistance.  I have only been flying this set-up for two years, so I can't comment on long-term survivability.

Chris

 

 

Chris Zavatson

N91CZ

360std

1150 hrs w/o a scratch