X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-bw0-f226.google.com ([209.85.218.226] verified) by logan.com (CommuniGate Pro SMTP 5.3.5) with ESMTP id 4194917 for flyrotary@lancaironline.net; Sun, 04 Apr 2010 02:53:58 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.226; envelope-from=lehanover@gmail.com Received: by bwz26 with SMTP id 26so2441034bwz.27 for ; Sat, 03 Apr 2010 23:53:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:date:received:message-id :subject:from:to:content-type; bh=4vm+r9qm0ariV+U4sJ4mn0lKGh4H/Zs1cVqmhOgD3a4=; b=oEqioY8Y7NJUj49Z4fGlbwCLlpoldJc49PCj8IBVqK90NabkrplPqZH2rvyYDrcIAT Is2KMPk6Rk2l/YsOMhbqcWAcyKtdGnEDUZrtaojpJ9EAGL5dcKPlHeL2IagbahQocz0v iX/x9WrHb+NT6qWkkykgqgDLLKuDy66gMoDsQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=rX3THrn69DToO3qYvgPLGzT3Dq0qaibfCMZ04VpiHbU8qEcGZAoWGhTo45jtyI/R4Z mhFeRXG1zdugfN6vcF168mUAd7TYh8ScMfZevYHJAsrBzhMnn0UygIitovXilvg3GYwa kMvOijfuGvuQbMoPsjbSwDWLxGR6IXyjquDeI= MIME-Version: 1.0 Received: by 10.204.118.131 with HTTP; Sat, 3 Apr 2010 23:53:21 -0700 (PDT) Date: Sun, 4 Apr 2010 02:53:21 -0400 Received: by 10.204.35.75 with SMTP id o11mr5062596bkd.214.1270364001301; Sat, 03 Apr 2010 23:53:21 -0700 (PDT) Message-ID: Subject: Multipal throats From: Lynn Hanover To: flyrotary@lancaironline.net Content-Type: multipart/alternative; boundary=00032555316a087431048363ab7f --00032555316a087431048363ab7f Content-Type: text/plain; charset=ISO-8859-1 Bill, On researching the Weber carb it seems it was originally developed to provide different chokes, one for low rpm and one for high rpm. That would be good if we had siamesed PP with different sized runners - sounds complicated. George ( down under) *The single throat for each housing is ideal for reducing complexity and limiting energy loss. * ** *The Webers with multipal throat sizes are for econemy at low speeds on the street. Very effective, and Ford and GM licensed the Weber DMSA-100 carb (one 23MM choke and one 27MM choke) for the Pinto and the Vega. Of course the Americans redesigned that carb instead of just buying it, and both were useless. Too many cooks you know..........* ** *There is little need of a strong mid range for aircraft use. The airplane is stuck in 2nd gear in effect by the reduction ratio. The prop loads build exponentially with RPM so, you need best power by 6,500 or 7,000 RPM tops, and best torque around cruise RPM. A big deal for a piston engine, nothing at all for a rotary if it is cooled and oiled properly.* ** *Lynn E. Hanover* --00032555316a087431048363ab7f Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
Bill,
On researching the Weber carb it = seems it was originally developed to
provide different chokes, one for = low rpm and one for high rpm.
That would be good if we had siamesed PP with different sized runners - sounds complicated.
George ( down under)
The single throat for each housing is ideal for reducing complexit= y and limiting energy loss.
=A0
The Webers with multipal throat sizes are for econemy at low speed= s on the street. Very effective, and Ford and GM licensed the Weber DMSA-10= 0 carb (one 23MM choke and one 27MM choke) for the Pinto and the Vega. Of c= ourse the Americans=A0redesigned that carb instead of just buying it, and b= oth were useless. Too many cooks you know..........
=A0
There is little need of a strong mid range for aircraft use. The a= irplane is stuck in 2nd gear in effect by the reduction ratio. The prop loa= ds build exponentially with RPM so, you need best power by 6,500 or 7,000 R= PM tops, and best torque around cruise RPM. A big deal for a piston engine,= nothing at all for a rotary if it is cooled and oiled properly.
=A0
Lynn E. Hanover
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