X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf18aec.mail.bellsouth.net ([205.152.59.66] verified) by logan.com (CommuniGate Pro SMTP 5.1.10) with ESMTP id 2164646 for flyrotary@lancaironline.net; Sun, 08 Jul 2007 00:57:10 -0400 Received-SPF: none receiver=logan.com; client-ip=205.152.59.66; envelope-from=rusty@radrotary.com Received: from ibm61aec.bellsouth.net ([65.6.194.9]) by imf18aec.mail.bellsouth.net with ESMTP id <20070708045631.EDBR28472.imf18aec.mail.bellsouth.net@ibm61aec.bellsouth.net> for ; Sun, 8 Jul 2007 00:56:31 -0400 Received: from rad ([65.6.194.9]) by ibm61aec.bellsouth.net with ESMTP id <20070708045631.VRPJ17420.ibm61aec.bellsouth.net@rad> for ; Sun, 8 Jul 2007 00:56:31 -0400 From: "Russell Duffy" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Stock Turbo Date: Sat, 7 Jul 2007 23:56:31 -0500 Message-ID: <001901c7c11c$59ed08a0$a301a8c0@rad> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001A_01C7C0F2.711700A0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6822 In-Reply-To: thread-index: AcfBEOijpWovUwIdQz+N+dGBRi91yQACToGQ Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138 This is a multi-part message in MIME format. ------=_NextPart_000_001A_01C7C0F2.711700A0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit The twin turbos are a sequential affair. One for low end, the other for high end. They are not intended to be both providing large amounts of boost simultanously. I do not know of any fliers who used twin turbos. Just a minor nit to pick. The FD sequential twins do both provide boost simultaneously. The primary comes in as early as possible, and the secondary joins it later. Basically, it's like having a small turbo for quick spool up on the low end, then the two small turbos essentially become one larger turbo at higher rpm. There's a nightmare of valves, solenoids, and hoses that make this happen, but when it works, it's a beautiful thing for a street machine :-) FWIW, I'm 100% in agreement that you don't want twin turbos on an aircraft unless the engine is so big that it's your only option for the amount of boost you want to run. I also agree that the stock turbo is not properly sized for aircraft use. Cheers, Rusty (I miss my FD, but I'd be in jail if I still had it...) ------=_NextPart_000_001A_01C7C0F2.711700A0 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Message
The twin turbos are a sequential affair. One for low end, the other = for=20 high end. They are not intended to be both providing large amounts of = boost=20 simultanously. I do not know of any fliers who used twin turbos. 
 
Just a minor=20 nit to pick.  The FD sequential twins do both provide boost=20 simultaneously.  The primary comes in as early as possible, and the = secondary joins it later.  Basically, it's like having a small = turbo for=20 quick spool up on the low end, then the two small turbos essentially = become one=20 larger turbo at higher rpm.  There's a nightmare=20 of valves, solenoids, and hoses that make this happen, but = when it=20 works, it's a beautiful thing for a street = machine :-)
 
FWIW, I'm=20 100% in agreement that you don't want twin turbos on an aircraft unless = the=20 engine is so big that it's your only option for the amount of boost = you=20 want to run.  I also agree that the stock turbo is not properly = sized for=20 aircraft use.   
 
Cheers,
Rusty (I miss=20 my FD, but I'd be in jail if I still had it...)
  =20
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