X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from cdptpa-omtalb.mail.rr.com ([75.180.132.123] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4124018 for flyrotary@lancaironline.net; Sat, 13 Feb 2010 12:58:43 -0500 Received-SPF: pass receiver=logan.com; client-ip=75.180.132.123; envelope-from=eanderson@carolina.rr.com Return-Path: X-Authority-Analysis: v=1.0 c=1 a=3n38PTu76SUA:10 a=ayC55rCoAAAA:8 a=arxwEM4EAAAA:8 a=QdXCYpuVAAAA:8 a=7g1VtSJxAAAA:8 a=ekHE3smAAAAA:20 a=UretUmmEAAAA:8 a=Ia-xEzejAAAA:8 a=5Up8faWwAAAA:8 a=nUuTZ29dAAAA:8 a=Wbs3AVlVpTGqSQYk0oYA:9 a=oi1DCMTdwEfDkFj1hH4A:7 a=v8vzMFgIB6kDLOdVzN2AnpdlFucA:4 a=4gPxjeWXNRoA:10 a=1vhyWl4Y8LcA:10 a=EzXvWhQp4_cA:10 a=UpFyRHORUArWBcFx:21 a=t9HNiudF8iqZ8UnR:21 a=SSmOFEACAAAA:8 a=apckJrF7AAAA:8 a=pbGKp9rIkhkYvseHdHoA:7 a=GMRNYLQWZXTK7cXpXumoW6rC2OoA:4 a=pu2laaUT1NY_xgpH:21 a=0nc5cG9-OLEgIPte:21 X-Cloudmark-Score: 0 X-Originating-IP: 75.191.186.236 Received: from [75.191.186.236] ([75.191.186.236:1090] helo=computername) by cdptpa-oedge01.mail.rr.com (envelope-from ) (ecelerity 2.2.2.39 r()) with ESMTP id 65/38-03217-F28E67B4; Sat, 13 Feb 2010 17:58:08 +0000 From: "Ed Anderson" Message-ID: <65.38.03217.F28E67B4@cdptpa-omtalb.mail.rr.com> To: "'Rotary motors in aircraft'" Subject: injector position was Re: Runner velocity Date: Sat, 13 Feb 2010 12:58:19 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0033_01CAACAC.37730E40" X-Mailer: Microsoft Office Outlook, Build 11.0.5510 Thread-Index: AcqszCnqAngXq4FnQY6ODhnKDjGscgACK1wg X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0033_01CAACAC.37730E40 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Jeff, you will probably get a number of views on this topic. There are those who believe injecting the fuel nearer the TB (further from the intake ports) will give better mixing of air and fuel and more importantly more time for the fuel to turn from liquid droplets to vapor/gas therefore better efficiency. There are others that believe whatever mixing benefit you get you lose something because now there is a longer run with metal walls to cause the fuel to adhere to the walls and not mix as completely. Like most things probably a bit of validity to both views. I have tired it both ways. I had a 75mm TB and four injectors sitting approx 18" from the intake ports. I could not tell if there were any increase in efficiency or power - there may have been but with the limitation of my instrumentation you just could not tell whether there was or not. It certainly wasn't significant. However, what I did encounter was if I suddenly opened the throttle, the engine would bog or hesitate - the engine never stopped, but I found that this used up more seat cushions on a go-a-rounds {:>). So I went back to putting the primary injectors in the block and secondary injectors as close as I could get to the intake ports. I personally like this arrangement. YMMV. My 0.02 worth 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 Jeff Luckey Sent: Saturday, February 13, 2010 11:46 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Runner velocity After reading this, a question comes to mind: What is the difference between throttle body injection and port injection? I've heard people say that w/ the injectors up near the TB, you get better fuel/air mixing. Is that an old-wives-tale? Which one makes more horsepower, gives better throttle response, etc? It seems to me that fabrication of intake manifold would be easier for injectors near the TB. Apparently there are benefits of port injection ('cause that's what the production engine uses) but I don't know what they are.. What are the pros and cons of each? BTW - Happy Birthday Ed :)! _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover Sent: Saturday, February 13, 2010 08:09 To: Rotary motors in aircraft Subject: [FlyRotary] Runner velocity http://home.earthlink.net/~mmc1919/venturi.html This is a free download of the Bernoulli Principal. Fun to play with and educational. The amount of fuel air entering the chamber is a function of runner cross section, velocity and time. The depression, or vacuum generated is a function of displacement and RPM. So the depression is about fixed by the 2606CCs and say, 6,000 RPM. The "M" in RPM is the time. So............ That leaves only Porting to increase intake open and closing time, (lengthen time period) and manufacturing the ideal intake runner set/ Throttle body combination. In my mind the runner size would be identical the the port opening for 4 to 6 inches out from the port opening. Then blend into one "D" shaped pipe for the 180 bend over the engine top. Then taper to a larger pipe of about 2 1/2" to blend into a plenum just big enough to fit the throttle body mounting plate. So, the cross section would be reduced gradually from the throttle body to the end of the "D" shape, then remain constant right up to the port opening. I would upset the inside radius of the "D" shape with a number of burs stood up with a three corner punch, to generate some tubulance.in order to keep flow attached. Just a guess. I could be completely wrong. Later, I tried a 75MM at one point and while it did nothing to improve engine power and performance, in my case it had an undesirable down side - now to be fair it could have been partially the results of having all 4 injectors back near the throttle body - but in any case, if you suddenly opened the throttle like in a panic go-a-round - the engine would bog and hesitate for a fraction of a second (seemed like minutes {:>)), the engine never stopped, but I just didn't like it. So I went back to the 65mm. So the important thing is to match your induction system to your real operating regime - NOT what you would in your wildest dream like for it to be {:>). Ed Anderson You are only 70?? Run hard and put away wet comes to mind.............. Lynn E. Hanover __________ 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_0033_01CAACAC.37730E40 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Jeff, you will probably get a = number of views on this topic.

 

There are those who believe = injecting the fuel nearer the TB (further from the intake ports) will give better = mixing of air and fuel and more importantly more time for the fuel to turn from = liquid droplets to vapor/gas  therefore better efficiency.  There are others = that believe whatever mixing benefit you get you lose something because now = there is a longer run with metal walls to cause the fuel to adhere to the walls = and not mix as completely.  Like most things probably a bit of validity to = both views.

 

I have tired it both ways.  I = had a 75mm TB and four injectors sitting approx 18” from the intake = ports.  I could not tell if there were any increase in efficiency or power = – there may have been but with the limitation of my instrumentation you = just could not tell whether there was or not.  It certainly wasn’t = significant.

 

However, what I did encounter was = if I suddenly opened the throttle, the engine would bog or hesitate – = the engine  never stopped, but I found that this used up more seat = cushions on a go-a-rounds {:>).  So I went back to putting the primary = injectors in the block and secondary injectors as close as I could get to the intake ports.  I personally like this arrangement. = YMMV.

 

My 0.02 = worth

 

Ed

 

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Jeff Luckey
Sent: Saturday, February = 13, 2010 11:46 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = Runner velocity

 

After reading this, a question = comes to mind:

 

What is the difference between = throttle body injection and port injection? I’ve heard people say that w/ = the injectors up near the TB, you get better fuel/air mixing.  Is that = an old-wives-tale?  Which one makes more horsepower, gives better = throttle response, etc?  It seems to me that fabrication of intake manifold = would be easier for injectors near the TB.

 

Apparently there are benefits of = port injection (‘cause that’s what the production engine uses) = but I don’t know what they are..

 

What are the pros and cons of = each?

 

 

BTW – Happy Birthday Ed = :)!

 

From: = Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Lynn Hanover
Sent: Saturday, February = 13, 2010 08:09
To: Rotary motors in aircraft
Subject: [FlyRotary] = Runner velocity

 

 

This is a free download of the Bernoulli Principal. Fun to play = with and educational.

 

The amount of fuel air entering the chamber is a function of = runner cross section, velocity and time.

 

The depression, or vacuum generated is a function of = displacement and RPM. So the depression is about fixed by the 2606CCs and say, 6,000 RPM. = The "M" in RPM is the time. = So............

 

That leaves only Porting to increase intake open and closing = time, (lengthen time period) and manufacturing the ideal intake runner set/ = Throttle body combination.

 

In my mind the runner size would be identical the the port = opening for 4 to 6 inches out from the port opening. Then blend into one = "D" shaped pipe for the 180 bend over the engine top. Then taper to a larger = pipe of about 2 1/2" to blend into a plenum just big enough to fit the = throttle body mounting plate.

 

So, the cross section would be reduced gradually from the = throttle body to the end of the "D" shape, then remain constant right up to = the port opening.

 

I would upset the inside radius of the "D" shape with = a number of burs stood up with a three corner punch, to generate some tubulance.in order to keep flow = attached.

 

Just a guess. I could be completely = wrong.

 

Later, I tried a 75MM at one point = and while it did nothing to improve engine power and performance, in my case = it had an undesirable down side – now to be fair it could have been = partially the results of having all 4 injectors back near the throttle body = – but in any case, if you suddenly opened the throttle like in a panic = go-a-round – the engine would bog and hesitate for a fraction of a second = (seemed like minutes {:>)), the engine never stopped, but I just didn’t = like it.  So I went back to the 65mm.

 

So the important thing is to match your induction system to = your real operating regime – NOT what you would in your wildest dream = like for it to  be {:>).

 

Ed Anderson

 

You are only 70?? =

Run hard and put away wet comes to mind..............

 

Lynn E. = Hanover



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

The message was checked by ESET NOD32 Antivirus.

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