Charge-air temps are EVERYTHING.  The flying rotary turbo guy should measure his. As you might imagine, 30-inches of MAP at 80F degrees is not at all the same thing as 30-inches of MAP at 140-150F degrees.  That's a pretty typical output temp for a well-matched turbo.  So yes, intercooling is a MUST.

Well, my intake temp at 30" MAP was 167F on a 90F day, so he's right on with his figures.   

Also, centrifugal compressors are way below 50% eff at less than 10" of boost. That's where most compressor maps start. Operating "off the map" is never a good thing.  It adds tremendous heat for no boost, a poor trade-off.  And yes, you are correct.  It would take a few pounds of boost just to make up for the density loss from heating.  About 10 psi with no intercooler, 3 psi with.

10 psi!!! Ack!  Must fit intercooler... 

Av gas give great margins of safety with boost.  We ran 50" MAP on car gas. Hey, testing to destruction [commonly shortened to just "testing"] is a BITCH, and not for everyone.  It only looks easy. ;-)

Well, I can verify that nothing blew up at 50" on the ground, with an intake temp around 250 F (est).   

Where are you measuring charge temp?

I stuck a thermocouple inside the hose from the turbo, where it connected to my pressurized airbox.   

  Is it not an input to Tracy's fuel control?

Yes, there is a temp sensor installed in the airbox.

 Can you capture and monitor it?

Not until the EM-2 arrives.

  Additionally, if you have excess heat rejection resources (oversize oil coolers, radiators, etc.) perhaps you could lighten up on that stuff and get some sort (any sort at all) of intercooler in there.  I haven't seen your installation, and am not even an RV guy, but it just seems as if there MUST be SOME way to get what you need in there without the cowl getting this thyroid condition you describe. 

OK, I'm certainly convinced enough to install an intercooler.  At the moment, I can probably put one in the right cheek, and add some duct to it, or I can mount it in front of the "extra" portion of the radiator.  I've spent a huge amount of time trying to figure out the best way to arrange cooling items in the rev-2 cowl, but haven't factored the intercooler into my thoughts at all.  I go ahead and find a way to mount one in BUC as a test, which is the logical way to help me decide what stays, and what goes when the rev-2 cowl comes along.  I'll find the 2nd and 3rd gen IC's in the attic, and see which one fits best.  I'll also try to measure them for whoever was asking the other day. 

Also, TT seems to confirm what a number of folks are suggesting that you can give it 6 or 8 psi of boost and see what happens - the chance of screwing anything up at that level seems pretty remote.

Roger.  Thanks again,

Rusty (a new reason to live)