Just got this note from Greg:
"My old notes show a TO-4E housing with a 55 compressor and P trim.  .81 A/R
ratio.  The rationale was for a pressure ratio < 3.0.  Given that MAP is dropping with altitude,
but our need for power is also dropping, we can use this turbo to provide 250++ HP for takeoff
while pushing a relaxed 180 HP through the air at altitude.

This is like flying a IO-360 on the deck except with less drag at the
higher elevation, so your TAS is much higher.  The .81 A/R keeps you out of
the surge range and in the middle of the 55 map.  A 1.0 A/R pushes you
closer to the edge of the map than I'd like to see."

I had also sent Greg a copy of Cliff Manzke's turbo notes from the Rotary 
Engine Best Practices site- 29/APR/2001, his comments were:

"I agree, as you know,  that a wastegate is decorative dead weight, but
disagree with his need for a larger intercooler.  He is making the same
error I made that you can avoid: cooling all the charge air.  Put your POV
_ahead_ of the cooler and cool only what you intend to run through the
rotorset." [POV = intake manifold Pop Off Valve. Limits intake 
manifold pressure]

So there you have it finally....

"TO-4E housing with a 55 compressor and P trim.  .81 A/R ratio."

...Chrissi

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

Thanks Crissi

Paul Lamar
 
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