Return-Path: Received: from [65.54.169.58] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.2.8) with ESMTP id 618696 for flyrotary@lancaironline.net; Sun, 23 Jan 2005 18:06:31 -0500 Received-SPF: pass receiver=logan.com; client-ip=65.54.169.58; envelope-from=lors01@msn.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Sun, 23 Jan 2005 15:06:00 -0800 Message-ID: Received: from 4.174.5.173 by BAY3-DAV28.phx.gbl with DAV; Sun, 23 Jan 2005 23:05:27 +0000 X-Originating-IP: [4.174.5.173] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: P Port fuel Injection Date: Sun, 23 Jan 2005 18:05:27 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00A8_01C50176.1E56F070" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MimeOLE: Produced By MSN MimeOLE V9.10.0009.2900 Seal-Send-Time: Sun, 23 Jan 2005 18:05:27 -0500 X-OriginalArrivalTime: 23 Jan 2005 23:06:00.0725 (UTC) FILETIME=[1AE09C50:01C501A0] This is a multi-part message in MIME format. ------=_NextPart_000_00A8_01C50176.1E56F070 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Below are the key points of my and Rolf's previous comments (at least I = think so) Tracy wrote : One important thing to note is that the air volume in the long runner = can be larger than the intake charge at low throttle. This makes it = virtually impossible to properly time the injection pulse of a "long = distance injector" without knowing the future, if you get my meaning. =20 Tracy (marking this down as #9999 on list of things to try) Rolf wrote: The funny thing is, if you spray at the bell mouth, it takes a complete = cycle for the air and fuel to reach the chamber. In other word, the = timing should be the same, but when you inject it will reach only the = next chamber, not the one it would serve if the injector is close to the = intake port. However, I see no problem with this. In fact due to the back flow you = may actually get the same effect as you get with a closed intake valve = at an RPE, where the fuel has time to evaporate, hence the better fuel = burn with a far away injector. Perhaps you should think about that for a while and get back to me, see = what you think. One thing though, I would ask Tracy about his beginning = and end of injection cycle relative to the crank angle at idle and at = full speed of 7500 rpm. I am very interested in how he timed his = injectors. Regards Rolf Tracy now: If I understand it correctly, we are in agreement about what happens = with injection at the intake end of the runner. However, I DO see a = problem with this at low speed where the fuel is delayed a full cycle - = "Shitty throttle response" to put it in non engineering terms. It is = my guess that P Port vs Side port is a non factor in this matter. In the EC2, I start the injection cycle slightly before the intake port = opens. In the industry literature, some advocate starting it even = sooner. =20 I did some limited testing of injection timing but found no improvement = over what I tried first. None of these tests were with "Far end " = injectors however. =20 As I said before, I'll mark that down as #9999 on my list of things to = try. Tracy (so many experiments, so little time) ------=_NextPart_000_00A8_01C50176.1E56F070 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable

Below are the key points of my and Rolf's previous comments = (at least=20 I think so)

Tracy wrote :

One important thing to note is that the air volume in the long = runner=20 can be larger than the intake charge at low throttle. This makes = it=20 virtually impossible to properly time the injection pulse of a "long = distance=20 injector" without knowing the future, if you get my=20 meaning.

Tracy (marking this down as #9999 on list of = things=20 to try)

Rolf wrote:

The funny thing is, if you spray at the bell mouth, it takes a = complete=20 cycle for the air and fuel to reach the chamber. In other word, the = timing=20 should be the same, but when you inject it will reach only the next = chamber, not=20 the one it would serve if the injector is close to the intake=20 port.

However, I see no problem with this. In fact due to the = back flow=20 you may actually get the same effect as you get with a closed intake = valve at an=20 RPE, where the fuel has time to evaporate, hence the better fuel burn = with a far=20 away injector.

Perhaps you should think about that for a while = and get=20 back to me, see what you think. One thing though, I would ask Tracy = about his=20 beginning and end of injection cycle relative to the crank angle at idle = and at=20 full speed of 7500 rpm. I am very interested in how he timed his=20 injectors.

Regards
Rolf

Tracy now:

If I understand it correctly, we are in agreement about what = happens with=20 injection at the intake end of the runner. However, I DO see = a=20 problem with this at low speed where the fuel is delayed a full = cycle =20 - "Shitty throttle response" to put it in non engineering = terms. It=20 is my guess that P Port vs Side port is a non factor in this = matter.

In the EC2, I start the injection cycle slightly = before the=20 intake port opens. In the industry literature, some advocate = starting it=20 even sooner.

I did some limited testing of injection timing but found no=20 improvement over what I tried first. None of these tests were = with=20 "Far end " injectors however.

As I said before, I'll mark that down as #9999 on my list of things = to=20 try.

Tracy (so many experiments, so little = time)

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