These cooling issues are not trivial to overcome and I am getting concerned if the rotary/PSRU is the right choice for me to make.  Do not get me wrong, I love the powerplant.  How can you not?  These integration issues are not simple to conquer.  How many robust aircraft are currently flying?  What aircraft are these?  Most members here are building or flying aircraft that will fly circles around the small 4-passenger tail dragger I plan to build.  In contrast you have far greater air speeds to cool a captive volume of water than my 100-125 knots.  Yet, I suspect I have more free volume to work with than the streamlined shape of the Lancair or Velocity.

I also wanted to ask about the PSRU.  Have Tracey's efforts stood the test of time?  It seemed to have some useful features but, the PSRU can be a source of challenges as well.  I noticed the Cozy Girls have passed this on but, have not remained on radar consistently to determine what its fate will be.

Rick