Return-Path: Received: from [24.25.9.101] (HELO ms-smtp-02-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.2b2) with ESMTP id 3180179 for flyrotary@lancaironline.net; Tue, 20 Apr 2004 07:52:53 -0400 Received: from EDWARD (clt25-78-058.carolina.rr.com [24.25.78.58]) by ms-smtp-02-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i3KBqokG010834 for ; Tue, 20 Apr 2004 07:52:51 -0400 (EDT) Message-ID: <003d01c426ce$01e12fb0$2402a8c0@EDWARD> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: intake ideas? Date: Tue, 20 Apr 2004 07:52:50 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_003A_01C426AC.7A940D50" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1409 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1409 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_003A_01C426AC.7A940D50 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I certainly understand and agree with your skepticism on the results of = one or even several flights. I once thought I had topped out at over = 200 MPH before I found I had forgotten to convert Farinheit to celceus = for the TAS equation. Just my experience with Larger vs small diameter tubes, your mileage may = vary. I do recall that Bill Eslick started out with a very short stack = and later found power improvments by going to a longer stack. You might = send him an e mail to get the details. Not trying to get you to change = your mind, just relaying my experience. There are many variables in induction tuning and unexpected results is = not uncommon {:>) Ed Ed Anderson RV-6A N494BW Rotary Powered Matthews, NC ----- Original Message -----=20 From: Russell Duffy=20 To: Rotary motors in aircraft=20 Sent: Monday, April 19, 2004 11:48 PM Subject: [FlyRotary] Re: intake ideas? Actually, Rusty. I have always been fuel injected. My first manifold = was using 50 mm twin throat TMW Webber throttle body (with 4 injectors), = a racing beat webber DOE manifold which I flew on a 86 six port block. = I only had one flight on that engine with the new (longer smaller = diameter) manifold before my HALTECH fuel injection system failed, so = did not get a good comparison.=20 Thanks. I was thinking that you changed injection systems at about = the same time as the intake, but couldn't remember exactly. =20 =20 However, on that one flight with the old engine and new manifold I = did note that my rate of climb increased by 300 fpm over the old = manifold. Certainly not a conclusive nor exhaust test and comparison, = but enough to convince me to keep the new manifold when I installed the = turbo block.=20 As good as this sounds, I've learned (the hard way) not to believe = anything I notice on any single flight. While I don't doubt that you = could have had some improvement, one flight is not enough to quantify = it, so I have to remain skeptical. =20 In just about every theory of induction tuning I have looked at (and = its been quite a few), if they agreed on anything - it was longer, = smaller diameter tubes favored torque at lower rpms and short, larger = diameter tubes favored power at the higher rpms. =20 This is a good general starting point I guess. I'm still bummed that = I can't run 7k rpm, but it just isn't efficient with the 2.17 drive, and = going to the 2.85 would undo the last 4 months of work, plus some. As = painful as it is, I have to draw the line somewhere, but it isn't = stopping me from dreaming about the next rotary powered plane. After = the Airbike, my sights are set on 300 mph :-) Rusty (too many plans, too little time and money) ------=_NextPart_000_003A_01C426AC.7A940D50 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I certainly understand and agree with = your=20 skepticism on the results of one or even several flights.  I once = thought I=20 had topped out at over 200 MPH before I found I had forgotten to convert = Farinheit to celceus for the TAS equation.
 
Just my experience with Larger vs small = diameter=20 tubes, your mileage may vary.  I do recall that Bill Eslick started = out=20 with a very short stack and later found power improvments by going to a = longer=20 stack.  You might send him an e mail to get the details.  Not = trying=20 to get you to change your mind, just relaying my = experience.
 
There are many variables in induction = tuning and=20 unexpected results is not uncommon {:>)
 
Ed
 
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
----- Original Message -----
From:=20 Russell=20 Duffy
Sent: Monday, April 19, 2004 = 11:48=20 PM
Subject: [FlyRotary] Re: intake = ideas?

Actually, Rusty.  I have = always been=20 fuel injected.  My first manifold was using 50 mm twin throat TMW = Webber=20 throttle body (with 4 injectors), a racing beat webber DOE manifold = which I=20 flew on a 86 six port block.  I only had one flight on that = engine with=20 the new (longer smaller diameter) manifold before my HALTECH fuel = injection=20 system failed, so did not get a good comparison. 
 
Thanks.  I was thinking that you = changed=20 injection systems at about the same time as the intake, but couldn't = remember=20 exactly.  
  
   However, on that one = flight with=20 the old engine and new manifold I did note that my rate of climb = increased by=20 300 fpm over the old manifold.  Certainly not a conclusive nor = exhaust=20 test and comparison, but enough to convince me to keep the new = manifold when I=20 installed the turbo block. 
 
As good as this sounds, I've learned (the = hard way) not=20 to believe anything I notice on any single flight.  While = I don't=20 doubt that you could have had some improvement, one flight is not = enough to=20 quantify it, so I have to remain skeptical. =20  
 
In just about every theory of = induction=20 tuning I have looked at (and its been quite a few), if they agreed on = anything=20 - it was longer, smaller diameter tubes favored torque at lower = rpms and=20 short, larger diameter tubes favored power at the higher=20 rpms.   
 
This is a good general starting point I = guess.  I'm=20 still bummed that I can't run 7k rpm, but it just isn't = efficient with=20 the 2.17 drive, and going to the 2.85 would undo the last 4 months of = work,=20 plus some.  As painful as it is, I have to draw the line = somewhere, but=20 it isn't stopping me from dreaming about the next rotary powered = plane. =20 After the Airbike, my sights are set on 300 mph=20 :-)
 
Rusty (too many plans, too little time and=20 money)
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