Yes it does add to the complexity of flying unless you want to
         get into microcomputer control of waste gates. So far I know
         of nothing like that off the shelf that will work with a turbo
         rotary in aircraft use.

         I think Gordon and maybe a few others on here have a turbo
    selection
         spread sheet for A/C use.

         Gordon, could you upload your spread sheet again?

         The thing to watch out for is turbine over speed. That makes
         car turbochargers the wrong choice for aircraft use as the car
    turbo
         charger turbine has too much HP for the compressor. This is done
         so the turbo charger will accelerate rapidly. In steady state
         use the turbo charger will over speed and the turbine will be
         destroyed. Several people have blown up stock turbo chargers in
    turbo
         rotary engines in aircraft use.

         Usually the turbo charged used is a TO4 for the 3 rotor but the
         compressor should be chosen to be larger than what one would find
         in car use. This slows the maximum RPM of the turbo charger to keep
         it within RPM limits for the given EGT. Another way of putting it
         from the turbine point of view is you want an A/R greater
         than one. This slows the air flow going into the turbine
         blades.

         A way of measuring this is record the temperature
         drop across the turbine. The higher the temperature drop
         the more powerful the turbine. Also it is a good idea to
         get a turbine tachometer to check and make sure the turbine
         RPM is within limits. This will pay off in the long run
         as your turbine will last longer.

         Here is a spread sheet from Dave Leonard.

         Also get a copy of this book.
         "Turbochargers" by Hugh MacInnes HP Books ISBN 0-89586-135-6

         To minimize oil coking use a synthetic oil like Idemitsu
         rotary engine oil or Mobile One. Also try to get a water cooled
         turbocharger housing. They are available for the TO4. The stock
         Mazda turbos are water cooled.

         Paul Lamar ...No rotor no motor.



         I'm not clear whether Don has p-port intake or not, and whether
    he is
         against p-port intake. If so, I don't really see p-port as
    being high
         risk at all, and might actually improve reliability by lowering
         temperature rise when boosted for a given horsepower produced by
         lowering pumping loses.

         As Paul has said, all rotaries until the Renesis already have
    p-port on
         the exhaust side..


         Matt-


          Paul and Don,

         Here's the Turbochart spreadsheet.

         If you have any questions about using it, or suggestions to improve
         it please let me know.

         I'm in the middle of completely revamping it to add the exhaust
    side
         so we can match turbines for turbocompounding. I also want to make
         it easier to use.

         Regards,

         Gordon.

Thanks Gordon,
This spread sheet is very helpful.  As I started plugging in numbers for
my 20B, I wasn't sure what numbers to use for the following:

Volumetric Efficiency
Air-Fuel Ratio
Compressor Efficiency

I sent the spreadsheet back in this e-mail with my number saved in it.
Can you look at it for me?  All my little colored boxes seem to fall
outside of the graph.  The GT4202 Turbo Chart seems to be closest since
the colored boxes are at least inside the graph.  Am I doing it right??
What does all this tell me?
Don

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