X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-ew0-f52.google.com ([209.85.215.52] verified) by logan.com (CommuniGate Pro SMTP 5.3.10) with ESMTP id 4598730 for flyrotary@lancaironline.net; Wed, 01 Dec 2010 14:10:02 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.215.52; envelope-from=msteitle@gmail.com Received: by ewy23 with SMTP id 23so4591843ewy.25 for ; Wed, 01 Dec 2010 11:09:27 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=Sp5gcI/eA7mXPdhAVoeRV8RGDmuGmk8Ga3a3KKPZUgY=; b=GkYtZ38TrvrtpQALTJFc9L2P8AiP6GlN8cM5RiBRHpqO23ttpJz6E1A2nFmytH5pse s751AXTCwRJAE97Sw2Dja4h59avagz3bIzZlw5eRet5euNP+7hiiG1Oop4y1mCvhWArl AfFA3ElftS8BhKw9DWoC00GG9nl4/kPRlnuMU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=Vjfse/oyKyhiqfbKG3X6TtZR0ui1vd3hCZapmp+JVhvduQJ0FvepPLWc8OmC/8nA7G Hz6tbbDzRcdubWjchPbBkgC4uGe9NKOrhLSfZ9GcXBwYrbv0Ky4Imt+wDtfzZELyiGyW CeFt5gRpzDGXxp60fxEWdbw+izvAHyL0x0Wjw= MIME-Version: 1.0 Received: by 10.213.108.144 with SMTP id f16mr4960758ebp.39.1291230566501; Wed, 01 Dec 2010 11:09:26 -0800 (PST) Received: by 10.213.34.212 with HTTP; Wed, 1 Dec 2010 11:09:26 -0800 (PST) In-Reply-To: References: Date: Wed, 1 Dec 2010 13:09:26 -0600 Message-ID: Subject: Re: [FlyRotary] Re: Modified header Calculations From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=000e0cd1fbbe3d4d2a04965e0ba5 --000e0cd1fbbe3d4d2a04965e0ba5 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable "That PPort sounds angry!" ...and it is! ;-) Mark On Wed, Dec 1, 2010 at 1:02 PM, Bill Bradburry wr= ote: > Mark, > > I watched the video as you started up in front of Chris=92 hangar and tax= ied > away. I then went back and watched the video where you made the flight 2 > years ago. The difference in the sound is way more than just volume! Th= at > PPort sounds angry! > > > > Bill B > > > ------------------------------ > > *From:* Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] *O= n > Behalf Of *Mark Steitle > *Sent:* Wednesday, December 01, 2010 12:44 PM > *To:* Rotary motors in aircraft > *Subject:* [FlyRotary] Re: Modified header Calculations > > > > Bill, > > > > Not sure what you're asking. My p-port will idle down to below 1000 rpm, > although not as smoothly as my side port 20B did, or like my LS1 Chevy V-= 8. > This thread was addressing WOT issues caused by an overly restrictive > exhaust system. Changing to my previous "tangential" exhaust made a HUGH > improvement in WOT power (exactly as the chart that Ed posted earlier > showed). I am now in the process of building an equal-length header/exha= ust > to maximize power at around 6500 rpm. The runners on my current exhasut = are > not all the same length and are made from 2.0 DIA .140" 304SS. The > new exhasut will be made of 625 inconel. > > > > I hope to get it right this time. > > > > Mark > > On Wed, Dec 1, 2010 at 11:23 AM, wrote: > > Mark, and group, > If p-ports are so difficult why was the first car with a rotary equiped > with them? P ports can be fairly tame if you put the throttle plate, > (butterfly or slide), close to the port, or in the port. The original > powersport guys put together an in-port butterfly that idled very well. I= n > fact Steve Beckham told me that when using their pendrolous damper they > could idle their p-port engine at 1000 RPM! Their p-ports were 1-5/8 > diameter. > Bill Jepson > > > > Finally, I liked their comment regarding the peripheral ported engines. = It > reads, "Traditionally relegated to speciality race cars, occasionally a > peripherally ported engine finds its way onto the street in some > high-performance vehicle. These engines are not, however, for the faint o= f > heart." LOL Not to worry, my heart is strong! > > Mark > > > > -----Original Message----- > From: Mark Steitle > To: Rotary motors in aircraft > Sent: Wed, Dec 1, 2010 8:37 am > Subject: [FlyRotary] Re: Modified header Calculations > > > Ed, > > It took a while, but my copy of Street Rotary - How to Build Maximum > Horsepower & Reliability into Mazda's 12A, 13B & Renesis Engines finally > arrived yesterday. Thanks for the recommendation. Lots of good info, > everyone on the list ought to order a copy and read it from cover to cove= r, > except for Lynn H. - he ought to write his own book on rotary engines. (= I'd > buy the first copy.) > > As you suggested, I've been reading the chapter on exhaust systems. I > found a paragraph that is right on target relating to what we've been > discussing (exhaust system restriction). They compare a 2-rotor wankel t= o a > 2 cylinder 4-stroke where both cylinders share the same exhaust port. > > Quote, "...the exhaust system on a 12A or 13B rotary engine is roughly > analogous to a two-cylinder piston engine in which both cylinders are ser= ved > by a single exhaust port. If cylinder #1 was in overlap period, and the > exhaust valve of the #2 cylinder then opened, high pressure gas would flo= w > from the #2 to #1 cylinders. A highly restrictive exhaust system would > aggravate the situation. This, the authors point out, is the major reaso= n > why a free-flowing exhaust system is so important in a rotary engine." T= his > explains why I saw such an improvement when switching exhaust systems. > > There is also much discussion on primary header length. Disregarding the > "long" header system as we don't have the room, the "short" header length > shown for a p-port engine is between 10 and 18 inches. So, your > calculations for header length seem to be right in the ballpark. Now I h= ave > to figure how to get the three very short primary tubes of 11 3/4" to > meet on the same tangent at the collector. > > Finally, I liked their comment regarding the peripheral ported engines. = It > reads, "Traditionally relegated to speciality race cars, occasionally a > peripherally ported engine finds its way onto the street in some > high-performance vehicle. These engines are not, however, for the faint o= f > heart." LOL Not to worry, my heart is strong! > > Mark > > > On Sun, Nov 21, 2010 at 7:53 AM, Ed Anderson > wrote: > > > Mark, > > I did some additional reading in the rotary book I recommended to you and= a > bit more head scratching on exhaust systems. > > I modified the tube length formula I used earlier to compensate for the > fact the rotary puts out two exhaust pulses per port per 720 deg cycle > compared to 1 for the piston engine. This in effect halved the length of > tube needed to get the same scavenging effect. > > Also using the recommended rotary book values for area of a rotary exhau= st > tube , I calculated the tube diameter which came out to 1.8". > > In any case, I have attached the spreadsheet with those modifications > > Ed > > > Edward L. Anderson > Anderson Electronic Enterprises LLC > 305 Reefton Road > Weddington, NC 28104 > http://www.andersonee.com > http://www.eicommander.com > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > > > > > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > --000e0cd1fbbe3d4d2a04965e0ba5 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
"That PPort sounds angry!"
=A0
...and it is!=A0 ;-)

Mark
On Wed, Dec 1, 2010 at 1:02 PM, Bill Bradburry <= span dir=3D"ltr"><bbradburry= @bellsouth.net> wrote:

Mark,

I watched the v= ideo as you started up in front of Chris=92 hangar and taxied away.=A0 I th= en went back and watched the video where you made the flight 2 years ago.= =A0 The difference in the sound is way more than just volume!=A0 That PPort= sounds angry!

=A0

Bill B

=A0

From:= Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark Steitle
Sent: Wednesday, December 0= 1, 2010 12:44 PM
To: Rot= ary motors in aircraft
Subject: [FlyRotary] Re: Modified header Calculations

=A0

Bill,

=A0

Not sure what you're asking.=A0 My p-port will id= le down to below 1000 rpm, although not as smoothly as my side port 20B did= , or like my LS1 Chevy V-8.=A0 This thread was=A0addressing WOT issues caus= ed by an overly=A0restrictive exhaust system.=A0 Changing to my previous &q= uot;tangential"=A0exhaust made a HUGH improvement in WOT power (exactl= y as=A0the chart that Ed posted earlier showed).=A0 I am now in the process= of building an equal-length=A0header/exhaust to maximize power at around 6= 500 rpm.=A0 The runners on my current=A0exhasut are not all=A0the same=A0le= ngth and are=A0made from 2.0 DIA .140" 304SS.=A0 The new=A0exhasut wil= l be made of 625 inconel.

=A0

I hope to get it right this time.=A0=A0=

=A0

Mark=A0=A0

On Wed, Dec 1, 2010 at 11:23 AM, <wrjjrs@aol.com> wrote:

Mark, and group,
If p-ports are so difficult why w= as the first car with a rotary equiped with them? P ports can be fairly tam= e if you put the throttle plate, (butterfly or slide), close to the port, o= r in the port. The original powersport guys put together an in-port butterf= ly that idled very well. In fact Steve Beckham told me that when using thei= r pendrolous damper they could idle their p-port engine at 1000 RPM! Their = p-ports were 1-5/8 diameter.
Bill Jepson



Finally, I like= d their comment=A0regarding the peripheral ported engines.=A0 It reads,=A0&= quot;Traditionally relegated to speciality race cars, occasionally a periph= erally ported engine finds its way onto the street in some high-performance= vehicle. These engines are not, however, for the faint of heart."=A0 = LOL=A0 Not to worry, my heart is strong!=A0
=A0=A0
Mark



-----Original Message-----
From: Mark Steitle <= msteitle@gmail.com<= /a>>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Wed, D= ec 1, 2010 8:37 am
Subject: [FlyRotary] Re: Modified header Calculations=


Ed,
=A0
It took a while, but my copy of=A0Street Rotary - How= to=A0Build Maximum Horsepower & Reliability into Mazda's 12A, 13B = & Renesis Engines=A0finally arrived yesterday.=A0 Thanks for the recomm= endation.=A0 Lots of good info, everyone on the list ought to order a copy = and read it from cover to cover, except for Lynn H. - he ought to write=A0h= is own=A0book on rotary engines.=A0 (I'd buy the first copy.)=A0
=A0
As you suggested, I've been reading the chapter on exhaust syste= ms.=A0 I found a paragraph that is right on target relating to what we'= ve been discussing (exhaust system restriction).=A0 They compare a 2-rotor = wankel to a 2 cylinder 4-stroke=A0where both cylinders share the same exhau= st port.=A0
=A0
Quote, "...the exhaust system on a 12A or 13B rotary engine is = roughly analogous to a two-cylinder piston engine in which both cylinders a= re served by a single exhaust port.=A0 If cylinder #1 was in overlap period= , and the exhaust valve of the #2 cylinder then opened, high pressure gas w= ould flow from the #2 to #1 cylinders.=A0 A highly restrictive exhaust syst= em would aggravate the situation.=A0 This, the authors point out, is the ma= jor reason why a free-flowing exhaust system is so important in a rotary en= gine."=A0 This explains why I saw such an improvement when switching e= xhaust systems.=A0
=A0
There is also much discussion on primary header length.=A0 Disregard= ing the "long" header system as we don't have the room, the &= quot;short" header length shown for a p-port engine is between 10 and = 18 inches.=A0 So, your calculations for header length seem to be right in t= he ballpark.=A0 Now I have to figure how to get the three very short primar= y tubes of 11 3/4" to meet=A0on the same tangent at the collector.=A0<= br> =A0
Finally, I liked their comment=A0regarding the peripheral ported eng= ines.=A0 It reads,=A0"Traditionally relegated to speciality race cars,= occasionally a peripherally ported engine finds its way onto the street in= some high-performance vehicle. These engines are not, however, for the fai= nt of heart."=A0 LOL=A0 Not to worry, my heart is strong!=A0
=A0=A0
Mark


On Sun, Nov 21, 2010 at 7:53 AM, Ed Anderson <= eanderson@ca= rolina.rr.com> wrote:


Mark,
=A0
I did some addition= al reading in the rotary book I recommended to you and a bit more head scra= tching on exhaust systems.
=A0
I modified the tube length=A0formula I=A0used earlier to compensate = for the fact the rotary puts out two exhaust pulses per port per 720 deg cy= cle compared to 1 for the piston engine.=A0 This in effect halved the lengt= h of tube needed to get the same scavenging effect.
=A0
Also using the recommended rotary =A0book values for area of a rotar= y exhaust tube=A0, I calculated the tube diameter which came out to 1.8&quo= t;.=A0
=A0
In any case, I have attached the spreadsheet with those mo= difications
=A0
Ed
=A0
=A0
Edward L. Anderson
Anderson Electronic Enterp= rises LLC
305 Reefton Road
Weddington, NC 28104
http://www.andersonee.com
http://www.eicommand= er.com


--
Homepage: =A0http://www.flyrotary.com/
Archive and UnSub: =A0 http://mail.lancaironline.net:81/lists/flyrotary/List.html






--
Homepage: =A0http://www.flyrotary.com/
Archive and UnSub:= =A0 http://mail.lancaironline.net:81/lists/flyrotary/List.ht= ml

=A0

<= br> --000e0cd1fbbe3d4d2a04965e0ba5--