Ernesto Sanchez wrote:

All these choices with different options can drive a person crazy.  Thank
you Chrissi for sending the Garrett catalog.  I was thinking of using TOE-50
or 60  Did you see the map for the GT7?  If you draw a vertical line up from
32 Lbs/min it looks like it would be hard to overspeed at altitude and looks
like it would be more efficient (less heat).  The TO4 housing 76mm, 52 trim,
0.70 A/R has the best pattern. The turbine with 1.12 looks good too.  I
think the only way to be sure is to dyno them in an altitude chamber.  I
wish I had the money.
Ernesto

Dear Ernesto,
Some notes from chats with Greg were that he was seeking a pressure ratio less than 3.0 and an A/R
in the neighborhood of .81 to stay clear of the surge range and closer to the middle of the map,
that a 1.0 A/R pushes too close to the edge of the map.
...Chrissi

Cozy Mk-IV 13B Turbo
www.CozyGirrrl.com
Chrissi@BlueMountainAvionics.com

 
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