X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [64.12.137.4] (HELO imo-m23.mail.aol.com) by logan.com (CommuniGate Pro SMTP 5.0.7) with ESMTP id 963815 for flyrotary@lancaironline.net; Wed, 01 Feb 2006 15:05:16 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.137.4; envelope-from=WRJJRS@aol.com Received: from WRJJRS@aol.com by imo-m23.mx.aol.com (mail_out_v38_r6.3.) id q.2bb.3d55ccd (16100) for ; Wed, 1 Feb 2006 15:04:27 -0500 (EST) Received: from mblk-r27 (mblk-r27.mblk.aol.com [152.163.179.17]) by air-id11.mx.aol.com (vx) with ESMTP id MAILINID114-3ee443e1144b277; Wed, 01 Feb 2006 15:04:27 -0500 Date: Wed, 01 Feb 2006 15:04:27 -0500 Message-Id: <8C7F581D6D24147-101C-FE82@mblk-r27.sysops.aol.com> From: wrjjrs@aol.com References: Received: from 66.127.99.234 by mblk-r27.sysops.aol.com (152.163.179.17) with HTTP (WebMailUI); Wed, 01 Feb 2006 15:04:27 -0500 X-MB-Message-Source: WebUI X-MB-Message-Type: User In-Reply-To: X-Mailer: AOL WebMail 15106 Subject: Re: [FlyRotary] Re: Cooling air inlets Content-Type: multipart/alternative; boundary="--------MailBlocks_8C7F581D6C3F343_101C_F6C4_mblk-r27.sysops.aol.com" MIME-Version: 1.0 To: flyrotary@lancaironline.net X-AOL-IP: 152.163.179.17 X-Spam-Flag: NO ----------MailBlocks_8C7F581D6C3F343_101C_F6C4_mblk-r27.sysops.aol.com Content-Type: text/plain; charset="us-ascii" Tracy, I really believe you will be better off with the round cowl inlets. What oil cooler are you using there? Powersport never had good cooling from that lower inlet. They used the firewall mounted radiator with rather poor ducting. I believe you would have to bottom mount the radiator and carefully duct it for the lower scoop cooler to work, and then only with an increase in cooling drag. Bill Jepson PS. What are the dims. on your radiator again? WRJ -----Original Message----- From: Tracy Crook To: Rotary motors in aircraft Sent: Wed, 1 Feb 2006 12:23:12 -0500 Subject: [FlyRotary] Re: Cooling air inlets Not that the purpose built cowl will not work but I felt that fitting and optimizing all the systems was more straight forward and easier with the 'classic' cowl. Not shown in the picture is the intake manifold which is similar to the one in my RV-4. It would stick out the side of the purpose built cowl. This is just one of many factors. Also, I think Will James who makes the purpose built cowl was still working out the rights to market it (it was originally for Powersport) when I got mine. Tracy ----- Original Message ----- From: Greg@itmack To: Rotary motors in aircraft Sent: Tuesday, January 31, 2006 4:59 PM Subject: [FlyRotary] Re: Cooling air inlets Tracy, just wondering why you went for the "classic" cowl instead of the Sam James purpose built rotary cowl? Greg Hi John, There are no ballpark figures, only arguments about them : ) FWIW, I am using a Sam James cowl with 5" round inlets and fervently hope that they will cool my 20B. Tracy (dangerously close to first engine start) ----- Original Message ----- From: John Downing To: Rotary motors in aircraft Sent: Sunday, January 29, 2006 8:06 PM Subject: [FlyRotary] Cooling air inlets I am modifying the cowling for the Tailwind. The air inlet holes are 2 5/8"s x 7.5"s for a total of app. 21.5 sq. inches. x 2 for a total of 43. I am looking at a 5 inch round hole which is the size that Same James is using for the O-320's, which would make the diffusers easier to fabricate. The round 5 " hole has approximately 19.3 sq inches x 2 for 38.6 sq. inches total, if my math is right. Is this a ball park figure for the water coolers (GM evaporators) on the Mazda 13 B engine. JohnD -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/ Attached Image: 20B_update.jpg [Image removed] ----------MailBlocks_8C7F581D6C3F343_101C_F6C4_mblk-r27.sysops.aol.com Content-Type: text/html; charset="us-ascii"
Tracy,
 I really believe you will be better off with the round cowl inlets. What oil cooler are you using there? Powersport never had good cooling from that lower inlet. They used the firewall mounted radiator with rather poor ducting. I believe you would have to bottom mount the radiator and carefully duct it for the lower scoop cooler to work, and then only with an increase in cooling drag.
Bill Jepson
PS. What are the dims. on your radiator again? WRJ 
 
-----Original Message-----
From: Tracy Crook <lors01@msn.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, 1 Feb 2006 12:23:12 -0500
Subject: [FlyRotary] Re: Cooling air inlets

Not that the purpose built cowl will not work but I felt that fitting and optimizing all the systems was more straight forward and easier with the 'classic' cowl.  Not shown in the picture is the intake manifold which is similar to the one in my RV-4.  It would stick out the side of the purpose built cowl.  This is just one of many factors.   Also, I think Will James who makes the purpose built cowl was still working out the rights to market it (it was originally for Powersport) when I got mine.
 
Tracy
----- Original Message -----
Sent: Tuesday, January 31, 2006 4:59 PM
Subject: [FlyRotary] Re: Cooling air inlets

Tracy, just wondering why you went for the "classic" cowl instead of the Sam James purpose built rotary cowl?
 
Greg

Hi John,
There are no ballpark figures, only arguments about them  : )
 
FWIW, I am using a Sam James cowl with 5" round inlets and fervently hope that they will cool my 20B.
 
Tracy  (dangerously close to first engine start)
----- Original Message -----
Sent: Sunday, January 29, 2006 8:06 PM
Subject: [FlyRotary] Cooling air inlets

I am modifying the cowling for the Tailwind.  The air inlet holes are 2 5/8"s x 7.5"s for a total of  app. 21.5 sq. inches. x 2 for a total of 43.  I am looking at a 5 inch round hole which is the size that Same James is using for the O-320's,  which would make the diffusers easier to fabricate.  The round 5 " hole has approximately 19.3 sq inches x 2 for 38.6 sq. inches total, if my math is right.  Is this a ball park figure for the water coolers (GM evaporators) on the Mazda 13 B engine.  JohnD
Attached Image: 20B_update.jpg
[Image removed]
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