X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.120] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3888031 for flyrotary@lancaironline.net; Fri, 16 Oct 2009 08:36:02 -0400 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.120; envelope-from=eanderson@carolina.rr.com Received: from computername ([75.191.186.236]) by cdptpa-omta02.mail.rr.com with ESMTP id <20091016123526562.BINL16243@cdptpa-omta02.mail.rr.com> for ; Fri, 16 Oct 2009 12:35:26 +0000 From: "Ed Anderson" To: "'Rotary motors in aircraft'" Subject: Stoich A/F Ratio?? : [FlyRotary] Re: where's the missing power? Date: Fri, 16 Oct 2009 08:35:28 -0400 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_003C_01CA4E3B.9DF4E5F0" X-Mailer: Microsoft Office Outlook, Build 11.0.5510 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Thread-Index: AcpOD+LMwA5AHPA+R1elMDUVxopwzQATF3Ew In-Reply-To: Message-Id: <20091016123526562.BINL16243@cdptpa-omta02.mail.rr.com> This is a multi-part message in MIME format. ------=_NextPart_000_003C_01CA4E3B.9DF4E5F0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi Mike, I guess I'm missing something - If your mixture monitor shows stoich at full throttle, then it's not solely an airflow problem - it appears to me that it's the lack of sufficient fuel. IF you are at stoich 14.7:1 A/F ratio then that means you have more oxygen available in your system to support burning more fuel = more power. You should be able to enrich the mixture particularly at full throttle (assuming you are wanting full power at full throttle) to around 12.65:1 air/fuel ratio for best power. I know you know all of this - that is why I am puzzled by your statement that you feel it's an airflow problem when on the surface with the Stoich ratio it would appear it's a lack of sufficient fuel. Ed. Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://www.dmack.net/mazda/index.html http://www.flyrotary.com/ http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.rotaryaviation.com/Rotorhead%20Truth.htm _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike Wills Sent: Thursday, October 15, 2009 11:22 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: where's the missing power? Sorry for my absence on a topic I started. My nephew had a skateboarding accident last weekend and is in the hospital in a chemically induced coma until his brain swelling is under control. And I thought car powered airplanes were dangerous. Stay away from skateboards. Tracy - My mixture monitor shows stoich at full throttle. I suspect an airflow issue rather than fuel. Al - my vacuum gauge is located in the plenum directly behind the throttle plates. Lynn - I agree that the TB inlet is horrible and needs a bell mouth. The inlet is also pretty obstructed by the cowl which isnt visible in the pics I sent. I think I'll make an attempt to clean this up some and see if it gets me anywhere. If not I'll live with it for a while. Kelly - always tough to determine if the problem is an engine issue or if the load is simply too much for the engine to overcome. I'm going to experiment with the shallow dive several have suggested and see what happens. Mike ----- Original Message ----- From: Bill Bradburry To: Rotary motors in aircraft Sent: Tuesday, October 13, 2009 4:21 PM Subject: [FlyRotary] Re: where's the missing power? Since you have the vacuum gauge, this article will help you use it for troubleshooting. http://autospeed.com/cms/A_2393/article.html Bill B _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen Sent: Tuesday, October 13, 2009 7:22 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: where's the missing power? I dont have a regular manifold pressure gauge, just an industrial type vacuum gauge ( I really gotta get an MP gauge). Anyway, the vacuum gauge was indicating 4" of vacuum. Where are you measuring the 4" vacuum? If it is near the ports it is no unusual; if it is out before the runners; something is wrong. Al __________ Information from ESET NOD32 Antivirus, version of virus signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ------=_NextPart_000_003C_01CA4E3B.9DF4E5F0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Hi = Mike,

 

I guess I’m missing something = - If your mixture monitor shows stoich at full throttle, then it’s not = solely an airflow problem – it appears to me that it’s the lack of = sufficient fuel. IF you are at stoich 14.7:1 A/F ratio then that means you have = more oxygen available in your system to support burning more fuel =3D more = power.   You should be able to enrich the mixture particularly at full throttle = (assuming you are wanting full power at full throttle) to around 12.65:1 air/fuel = ratio for best power.  I know you know all of this - that is why I am = puzzled by your statement that you feel it’s an airflow problem when on the = surface with the Stoich ratio it would appear it’s a lack of sufficient = fuel. 

 

 

 

Ed.  =

 

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mike Wills
Sent: Thursday, October = 15, 2009 11:22 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = where's the missing power?

 

Sorry for my absence on a topic I started. My = nephew had a skateboarding accident last weekend and is in the hospital in a chemically induced coma until his brain swelling is under control. And I thought car powered airplanes were dangerous. Stay away from = skateboards.

 

Tracy - My mixture monitor shows stoich at full throttle. I suspect an airflow = issue rather than fuel.

 

Al - my vacuum gauge is located in the plenum = directly behind the throttle plates.

 

Lynn - I agree that the TB inlet is horrible and needs a bell mouth. The inlet is also = pretty obstructed by the cowl which isnt visible in the pics I sent. I think = I'll make an attempt to clean this up some and see if it gets me anywhere. If not = I'll live with it for a while.

 

Kelly - always tough to determine if the problem is = an engine issue or if the load is simply too much for the engine to = overcome. I'm going to experiment with the shallow dive several have suggested and see = what happens.

 

Mike

----- Original Message ----- =

Sent: = Tuesday, October 13, 2009 4:21 PM

Subject: = [FlyRotary] Re: where's the missing power?

 

Since you have the vacuum gauge, this article will help you use = it for troubleshooting.

 

 http://autospeed.co= m/cms/A_2393/article.html

 

Bill B

 

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Tuesday, October = 13, 2009 7:22 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = where's the missing power?

I dont have a regular = manifold pressure gauge, just an industrial type vacuum gauge ( I really gotta = get an MP gauge). Anyway, the vacuum gauge was indicating 4" of = vacuum.

 

Where are you measuring the = 4” vacuum?  If it is near the ports it is no unusual; if it is out = before the runners; something is wrong.

 

Al



__________ Information from ESET NOD32 Antivirus, version of virus = signature database 3267 (20080714) __________

The message was checked by ESET NOD32 Antivirus.

http://www.eset.com

------=_NextPart_000_003C_01CA4E3B.9DF4E5F0--