Return-Path: <13brv3@bellsouth.net> Received: from imf21aec.mail.bellsouth.net ([205.152.59.69] verified) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 2898560 for flyrotary@lancaironline.net; Sat, 20 Dec 2003 11:09:58 -0500 Received: from rad ([68.212.7.74]) by imf21aec.mail.bellsouth.net (InterMail vM.5.01.06.05 201-253-122-130-105-20030824) with ESMTP id <20031220160957.YBFJ7487.imf21aec.mail.bellsouth.net@rad> for ; Sat, 20 Dec 2003 11:09:57 -0500 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: spintech, and exhaust size Date: Sat, 20 Dec 2003 10:09:57 -0600 Message-ID: <01d301c3c713$b6808d50$6001a8c0@rad> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_01D4_01C3C6E1.6BE61D50" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.4510 X-MIMEOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 Importance: Normal In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_01D4_01C3C6E1.6BE61D50 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Mine spintech is a little smaller than Tracy's but I don't remember how much. Again, as I remember the guy at Spintech didn't care about = aircraft use. Also, there was no scientific reason for the two inch in/out, and = some have recommended a smaller diameter, like 1.5 to 1.75.=20 =20 =20 Thanks for the info Tommy. The non-scientific reason for your 2" in/out = may have been that it's the minimum size Spintech lists :-) =20 =20 I have a couple Racing Beat header flanges, and they have 2-1/8" holes. I'll look at the actual port size, and see if maybe that can be cut down = a bit. The smaller diameter pipe would be easier to work with, but I certainly don't want to make it so small that it hurts the flow at 7500 = rpm. =20 What diameter pipe are you guys using? Larger size after collector?=20 =20 As for collectors, refer to the Spintech link- http://www.spintechmufflers.com/spintech/styleimages/index.htm =20 Would #9 "Y-Collector/Center" be an effective collector, or is there not enough pipe after the two join together to provide a good scavenging = effect? =20 Do you get any scavenging effect at all out of a design like #7, with = dual inlets, and one outlet. =20 =20 If you used a design like #10, with dual inlets and dual outlets, and = then put a collector after the outlets. Would get any scavenging effect? =20 =20 Sorry for all the questions, but I have a lot of catching up to do on exhaust design. =20 =20 I plan to be down your way the week after Christmas to fly again. Maybe bring it to NC if it proves itself well enough. Regards,=20 Tommy<><=20 =20 Good luck. I'm sure you'll be happy to have the airplane at your new = home. =20 Cheers, Rusty (I'm already exhausted... sorry) ------=_NextPart_000_01D4_01C3C6E1.6BE61D50 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable Message
Mine = spintech is=20 a little smaller than Tracy's but I don't remember how much. Again, as I = remember the guy at Spintech didn't care about aircraft use.  Also, = there=20 was no scientific reason for the two inch in/out, and some have = recommended a=20 smaller diameter, like 1.5 to 1.75. 
 
 
Thanks for the info Tommy. =20 The non-scientific reason for your 2" in/out may have been = that it's=20 the minimum size Spintech lists :-)  =
 
I have a couple Racing Beat header flanges, = and they=20 have 2-1/8" holes.  I'll look at the actual port size, and see if = maybe=20 that can be cut down a bit.  The smaller diameter pipe would = be easier=20 to work with, but I certainly don't want to make it so small that = it hurts=20 the flow at 7500 rpm.   
 
What diameter pipe are you guys=20 using?  Larger size after = collector? 
 
As for collectors, refer to the Spintech = link- h= ttp://www.spintechmufflers.com/spintech/styleimages/index.htm<= /FONT>
 
Would #9 "Y-Collector/Center" be an = effective=20 collector, or is there not enough pipe after the two join together to = provide a=20 good scavenging effect?   
 
Do you get any scavenging effect at all out = of a design=20 like #7, with dual inlets, and one outlet.  =
 
If you used a design like #10, with dual = inlets=20 and dual outlets, and then put a collector after the outlets.  = Would get=20 any scavenging effect?  
 
Sorry for all the questions, but I have a lot = of=20 catching up to do on exhaust design. =   
 
I = plan to be down=20 your way the week after Christmas to fly again.  Maybe bring it to = NC if it=20 proves itself well enough.
Regards,=20
Tommy<>< 
 
Good luck.  I'm sure you'll be happy=20 to have the airplane at your new=20 home.   
 
Cheers,
Rusty (I'm already exhausted...=20 sorry)
------=_NextPart_000_01D4_01C3C6E1.6BE61D50--