Return-Path: Received: from relay02.roc.ny.frontiernet.net ([66.133.131.35] verified) by logan.com (CommuniGate Pro SMTP 4.1.3) with ESMTP id 2590095 for flyrotary@lancaironline.net; Mon, 22 Sep 2003 23:42:09 -0400 Received: (qmail 24447 invoked from network); 23 Sep 2003 03:42:09 -0000 Received: from unknown (HELO frontiernet.net) ([67.50.124.115]) (envelope-sender ) by relay02.roc.ny.frontiernet.net (FrontierMTA 2.3.6) with SMTP for ; 23 Sep 2003 03:42:09 -0000 Message-ID: <3F6FB38D.4A2EB295@frontiernet.net> Date: Mon, 22 Sep 2003 22:44:29 -0400 From: Jim Sower X-Mailer: Mozilla 4.77 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Some turbo thoughts from a pro .... References: Content-Type: multipart/alternative; boundary="------------88507FBC2B66743D5CDE314E" --------------88507FBC2B66743D5CDE314E Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I don't have numbers any more. That was long ago in a different life, but they're available - probably from Ed :o) Just looking at my take off performance between 70 F and 90 F, I'd guess that your 88% isn't far off. But then again, I've already told you more than I know :o) If it flies, get it up to 2000' or so overhead the air patch and pour the coals to it. Give it 18" - 20" of boost and see how it climbs. See you at Tracy's ... Jim S. Russell Duffy wrote: > > > 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. > > Speaking of temps, I meant to ask about the calculations. > What would be the theoretical loss of available power between > 30" MAP at 90F, and 30" MAP at 167F? I attempted to calculate > this, and came up with only having 88% power at 167F compared > to 90F. I'm only about .0348% confident in this calculation > though. It sounds like Finn is seeing a much larger > difference, and I've always been able to feel the diff in cars > between hot and cold days. To feel the diff in a car would > seem to suggest quite a bit of power to me. Thanks,Rusty -- Jim Sower Crossville, TN; Chapter 5 Long-EZ N83RT, Velocity N4095T --------------88507FBC2B66743D5CDE314E Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit I don't have numbers any more. That was long ago in a different life, but they're available - probably from Ed :o) Just looking at my take off performance between 70 F and 90 F, I'd guess that your 88% isn't far off. But then again, I've already told you more than I know :o) If it flies, get it up to 2000' or so overhead the air patch and pour the coals to it. Give it 18" - 20" of boost and see how it climbs.
See you at Tracy's ... Jim S.

Russell Duffy wrote:

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.
Speaking of temps, I meant to ask about the calculations. What would be the theoretical loss of available power between 30" MAP at 90F, and 30" MAP at 167F? I attempted to calculate this, and came up with only having 88% power at 167F compared to 90F. I'm only about .0348% confident in this calculation though. It sounds like Finn is seeing a much larger difference, and I've always been able to feel the diff in cars between hot and cold days. To feel the diff in a car would seem to suggest quite a bit of power to me. Thanks,Rusty

--
Jim Sower
Crossville, TN; Chapter 5
Long-EZ N83RT, Velocity N4095T
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