X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-m24.mx.aol.com ([64.12.137.5] verified) by logan.com (CommuniGate Pro SMTP 5.2.3) with ESMTP id 2919730 for flyrotary@lancaironline.net; Tue, 13 May 2008 02:20:03 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.137.5; envelope-from=Lehanover@aol.com Received: from Lehanover@aol.com by imo-m24.mx.aol.com (mail_out_v38_r9.4.) id q.bfd.3157511b (30737) for ; Tue, 13 May 2008 02:19:24 -0400 (EDT) From: Lehanover@aol.com Message-ID: Date: Tue, 13 May 2008 02:19:23 EDT Subject: Re: [FlyRotary] Exhaust Progress To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1210659563" X-Mailer: 9.0 for Windows sub 5132 X-Spam-Flag: NO -------------------------------1210659563 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Actually the two 180s are used by all builders as a gag to get systems to the equal length they want. As the 180s look and act as the slide on a trombone. How cool is that? The idea is to get at least two complete exhaust cycles into each header before the collector. This is a target that moves up with RPM, so the longest length is needed at the lower end of the RPM range and there may be three or more cycles in the header at the top end. You can build an 11" primary system and get the job done with one cycle, but the lengths and angles must be very accurate. The long collector tends to allow the ideal length to be less of a factor in scavenging than a short collector. You have a short collector. So your system will tend to provide the very best performance over a small range of RPM. I would cut through the collector about half way down and extend it to be at least a third longer than it is now. I would build a two tube support and a saddle to support the tubes just ahead of the collector. When the engine shakes, the whole system must move with the engine. At a long distance from the flanges it moves quite a distance and without support it applies a great amount of stress right at the welds into the flanges. The very worst place to get a failure. A failure here progresses to complete failure in seconds. This will not go unnoticed, like a 6,000 round machine gun next to your ear. Any support must be attached to the engine block, so everything moves together. Two ball joints to a fixed muffler is good. Even a soft mounting for the muffler would help reduce stresses further. Chamfer the downstream ends of the tube junctions with a die grinder. Just a bit so there are no edges showing to the flow, which will be supersonic right into the muffler. Remember the line of sight transfer of heat, and shield anything that is exposed to the exhaust system. It looks really nice to me and will work better than most I have seen. Lynn E. Hanover In a message dated 5/12/2008 9:54:52 PM Eastern Daylight Time, DLOMHEIM@aol.com writes: I have finally cut had the time to cut out the 304 SS (.120 thickness) I purchased some months ago and am now ready for my welding buddy to bring his TIG welder over and tack it up. The overall length is about 22" on the firewall side pipe, but 21.25" on the "front" pipe, so I plan on cutting the collector about 3/4 inches long on one side to even them up. Overall the collector will have to shortened up considerably to achieve the more optimum 24 inch length Lynn has talked about for lower RPM / HP applications such as mine. Maybe Lynn could chime in here and comment on where on the collector that 24 inch point should be located for 5500-6000 rpm operations. Hopefully where the collector first opens up between the two pipes... **************Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001) -------------------------------1210659563 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
 
Actually the two 180s are used by all builders as a gag to get systems=20= to the equal length they want. As the 180s look and act as the slide on a tr= ombone. How cool is that?
 
The idea is to get at least two complete exhaust cycles into each heade= r before the collector. This is a target that moves up with RPM, so the long= est length is needed at the lower end of the RPM range and there may be thre= e or more cycles in the header at the top end. You can build an 11" primary=20= system and get the job done with one cycle, but the lengths and angles must=20= be very accurate. The long collector tends to allow the ideal length to be&n= bsp;less of a factor in scavenging than a short collector. You have a short=20= collector. So your system will tend to provide the very best performance ove= r a small range of RPM.
I would cut through the collector about half way down and extend it to=20= be at least a third longer than it is now. I would build a two tube support=20= and a saddle to support the tubes just ahead of the collector. When the engi= ne shakes, the whole system must move with the engine. At a long distance fr= om the flanges it moves quite a distance and without support it applies= a great amount of stress right at the welds into the flanges.
The very worst place to get a failure. A failure here progresses to com= plete failure in seconds. This will not go unnoticed, like a 6,000 round mac= hine gun next to your ear. Any support must be attached to the engine block,= so everything moves together. Two ball joints to a fixed muffler is good. E= ven a soft mounting for the muffler would help reduce stresses further.
 
Chamfer the downstream ends of the tube junctions with a die grinder. J= ust a bit so there are no edges showing to the flow, which will be supersoni= c right into the muffler. Remember the line of sight transfer of heat,=20= and shield anything that is exposed to the exhaust system. It looks really n= ice to me and will work better than most I have seen.
 
Lynn E. Hanover 
 
 
In a message dated 5/12/2008 9:54:52 PM Eastern Daylight Time, DLOMHEIM= @aol.com writes:
I have finally cut had the time to cut out=20= the 304 SS (.120 thickness) I purchased some months ago and am now ready for= my welding buddy to bring his TIG welder over and tack it up.  The ove= rall length is about 22" on the firewall side pipe, but 21.25" on the "= front" pipe, so I plan on cutting the collector about 3/4 inc= hes long on one side to even them up.  Overall the collector will=20= have to shortened up considerably to achieve the more optimum 24 inch l= ength Lynn has talked about for lower RPM / HP applications such as mine.&nb= sp; 
 
Maybe Lynn could chime in here and comment=20= on where on the collector that 24 inch point should be located for 5500= -6000 rpm operations.  Hopefully where the collector first opens up bet= ween the two pipes...



Wondering what's for Dinner= Tonight? Get new twists on family favorites at AOL Food.<= /FONT>
-------------------------------1210659563--