X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.121] verified) by logan.com (CommuniGate Pro SMTP 5.4c3j) with ESMTP id 4947512 for flyrotary@lancaironline.net; Fri, 15 Apr 2011 14:53:12 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.121; envelope-from=eanderson@carolina.rr.com Return-Path: X-Authority-Analysis: v=1.1 cv=ToWar1fa9ljTHbeJIRNQycBnYxCRNi5M/11QAwRcJ6A= c=1 sm=0 a=5qYtEaTt718A:10 a=rPkcCx1H5rrOSfN0dPC7kw==:17 a=ayC55rCoAAAA:8 a=qqTygoZRPiA9mewOXYIA:9 a=eFaoYg3pBTpZL0hI3VYA:7 a=wPNLvfGTeEIA:10 a=-6d3IzDUtJ0mFVpP:21 a=M2414emhO6fFkGWP:21 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=G5hSoLbkSFg44noM0qIA:9 a=w9AtRlsRex6PNAJEOrsA:7 a=MSl-tDqOz04A:10 a=EzXvWhQp4_cA:10 a=rPkcCx1H5rrOSfN0dPC7kw==:117 X-Cloudmark-Score: 0 X-Originating-IP: 174.110.167.5 Received: from [174.110.167.5] ([174.110.167.5:53848] helo=EdPC) by cdptpa-oedge04.mail.rr.com (envelope-from ) (ecelerity 2.2.3.46 r()) with ESMTP id C7/00-29678-4F398AD4; Fri, 15 Apr 2011 18:52:36 +0000 Message-ID: <3210EB54D5E545739747929CB1C65312@EdPC> From: "Ed Anderson" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: 16X Torque and Fuel Economy Date: Fri, 15 Apr 2011 14:52:24 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01CBFB7C.BB0ABA30" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 This is a multi-part message in MIME format. ------=_NextPart_000_0007_01CBFB7C.BB0ABA30 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I can understand your skepticism, William and they may well be overly = "optimistic" about fuel economy with the 16X as well. =20 However, higher torque, the direct injection and the improved = combustion chamber geometry (and less rpm as you point out) should = provide some improvement over the current design - and any improvement = would only make it better for aircraft usage.=20 But, regardless as to whether the claims for increase economy pan out = or not - so long as it brings the torque/power increase and lower = weight, the old iron in my Rv-6A will get replaced by the 16X - provided = they do it within the next 3-4 years. We will see. Ed From: William Wilson=20 Sent: Friday, April 15, 2011 2:07 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: 16X Torque and Fuel Economy The claimed fuel economy improvement in the Renesis was not really found = at all. In fact, most RX-8's got worse fuel economy than non-turbo = RX-7's (and quite a few of the turbo ones). Partly this is because the = RX-8 is a heavier car than the RX-7, but basically the Renesis is just = not all that efficient in real-world conditions. Maybe in the lab. Because of the generally disappointing performance of the Renesis engine = - which was less efficient, less reliable, and less powerful than = originally advertised, and on two of those three categories also = compares unfavorably to the (then) 40 year old 13B design, I have = somewhat of a skeptical attitude toward the 16X. Certainly I think the concept - increase the eccentricity for more = torque and less revs - makes sense. The existing Renesis was limited in = RPM more by the available transmissions than by its own capabilities, = and thermodynamic efficiency (already the weak point of the rotary = design) decreases at high RPM. Even with a "long stroke" design the 16X = will still be a high revving, free wheeling engine and should retain = most of the rotary character. But Mazda hasn't produced a genuinely good rotary engine in 20 years. I = admire their dedication, but they really need to start getting it right. On Fri, Apr 15, 2011 at 10:13 AM, Ed Anderson = wrote: Mazda claims that the 16X will have double the torque (at all rpm) and = better fuel economy at high engine speeds. The Renesis claimed a 20% = fuel improvement - but it appeared that was to be found at lower rpm = than we operate at. So hopefully the 16X will be kinder at our rpm = range. ------=_NextPart_000_0007_01CBFB7C.BB0ABA30 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I can understand your skepticism, William and = they may=20 well be overly "optimistic" about fuel economy with the 16X as = well. =20
 
However, higher torque,  the direct = injection and the=20 improved combustion chamber geometry (and less rpm as you point out)=20  should provide some improvement over the current design - and any=20 improvement would only make it better for aircraft = usage. 
 
 But, regardless as to whether the claims = for=20 increase economy pan out or not - so long as it brings the torque/power = increase=20 and lower weight, the old iron in my Rv-6A will get replaced by the 16X = -=20 provided they do it within the next 3-4 years.
 
We will see.
 
Ed
 
 

Sent: Friday, April 15, 2011 2:07 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: 16X Torque and Fuel=20 Economy

The claimed fuel economy improvement in the Renesis was = not=20 really found at all.  In fact, most RX-8's got worse fuel economy = than=20 non-turbo RX-7's (and quite a few of the turbo ones).  Partly this = is=20 because the RX-8 is a heavier car than the RX-7, but basically the = Renesis is=20 just not all that efficient in real-world conditions.  Maybe in the = lab.

Because of the generally disappointing performance of the = Renesis=20 engine - which was less efficient, less reliable, and less powerful than = originally advertised, and on two of those three categories also = compares=20 unfavorably to the (then) 40 year old 13B design, I have somewhat of a = skeptical=20 attitude toward the 16X.

Certainly I think the concept - increase = the=20 eccentricity for more torque and less revs - makes sense.  The = existing=20 Renesis was limited in RPM more by the available transmissions than by = its own=20 capabilities, and thermodynamic efficiency (already the weak point of = the rotary=20 design) decreases at high RPM.  Even with a "long stroke" design = the 16X=20 will still be a high revving, free wheeling engine and should retain = most of the=20 rotary character.

But Mazda hasn't produced a genuinely good = rotary=20 engine in 20 years.  I admire their dedication, but they really = need to=20 start getting it right.

On Fri, Apr 15, 2011 at 10:13 AM, Ed Anderson = <eanderson@carolina.rr.com&g= t;=20 wrote:
Mazda claims that the 16X will have double the = torque=20 (at all rpm) and better fuel economy at high engine speeds.  The = Renesis=20 claimed a 20% fuel improvement - but it appeared that was to be found = at lower=20 rpm than we operate at.  So hopefully the 16X will be kinder at = our rpm=20 range.
 
 

 
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