X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from aspensprings.uwyo.edu ([129.72.10.32] verified) by logan.com (CommuniGate Pro SMTP 5.2.12) with ESMTPS id 3497357 for flyrotary@lancaironline.net; Tue, 17 Feb 2009 12:31:24 -0500 Received-SPF: none receiver=logan.com; client-ip=129.72.10.32; envelope-from=SBoese@uwyo.edu Received: from ponyexpress-ht1.uwyo.edu (ponyexpress-ht1.uwyo.edu [10.84.60.208]) by aspensprings.uwyo.edu (8.13.8/8.13.8) with ESMTP id n1HHRho1008266 for ; Tue, 17 Feb 2009 10:30:41 -0700 (MST) (envelope-from SBoese@uwyo.edu) Received: from TELEGRAPH1.uwyo.edu (10.84.60.121) by ponyexpress-ht1.uwyo.edu (10.84.60.208) with Microsoft SMTP Server id 8.1.340.0; Tue, 17 Feb 2009 10:30:15 -0700 Received: from UWMAIL.uwyo.edu ([172.26.4.76]) by TELEGRAPH1.uwyo.edu with Microsoft SMTPSVC(6.0.3790.3959); Tue, 17 Feb 2009 10:30:15 -0700 Received: from Boesexps ([10.4.44.41]) by UWMAIL.uwyo.edu with Microsoft SMTPSVC(6.0.3790.3959); Tue, 17 Feb 2009 10:30:15 -0700 From: sboese To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Second flight Date: Tue, 17 Feb 2009 10:29:50 -0700 Message-ID: <5B4030CC3EE84B1DA87D8D9CFD88E0B7@gg.uwyo.edu> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001C_01C990EA.AA2CA790" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 Importance: Normal X-OriginalArrivalTime: 17 Feb 2009 17:30:15.0364 (UTC) FILETIME=[6526F840:01C99125] ------=_NextPart_000_001C_01C990EA.AA2CA790 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Tracy, =20 I have always wondered why so many people seem to have trouble with = staging, myself included. My setup uses all four injectors of the same part = number and the flow rates and dynamic ranges are very well matched as = demonstrated on a flow bench. =20 =20 As you know, I am in the process of retuning my system after an EC2 = upgrade. When looking at data logged from the EC2 at less than 1 second = intervals, there appears to be an inconsistency in the manifold pressure = corresponding to the staging address and the manifold pressure the EC2 reports when staging actually takes place. In my case staging will take place with = the manifold pressure reported by the EC2 up to 4 In Hg less than that corresponding to the staging address. So far I have not seen the system stage at the manifold pressure corresponding to the staging address. =20 Is it possible that the EC2 is actually staging at a lower manifold = pressure than that set in the staging address, using the mixture correction table value at that lower address, and when the manifold pressure rises sufficiently, the correct correction table addresses are used again? = With my mixture correction table, a significant increase in table values is required just above the staging threshold. If the above were happening, = the mixture would go very lean when the EC2 staged and used the values in = the correction table lower than the staging address. This is what I see on = the O2 sensors when there is a problem staging. =20 I hadn't tried to change mode 6 settings since I am sure my injectors = are very well matched and the manual indicates that in this case mode 6 = changes shouldn't be needed. Your message brings up the thought that if the = above is happening, one may be able to use mode 6 to obtain a mixture = correction table where there is no or very little change in table values for = addresses in the region corresponding to the staging point and a couple of inches = of manifold pressure below that. Then it wouldn't matter exactly what = manifold pressure the EC2 actually staged at or the actual correction table value used since the mixture would still be close to correct. Mode 1 or 9 may still be able to obtain correct mixtures outside this region. Is it possible that those who have no staging issues have stumbled on this = type of mixture correction table accidentally? =20 Crawling back into my hole to continue to RTFM. =20 Steve Boese =20 =20 =20 =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook Sent: Tuesday, February 17, 2009 9:30 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Second flight =20 Again, it is very important to understand what is happening. Without = this understanding, a builder is working in the dark. Fuel delivery is not doubled when the EC2/3 goes from staged (2 = injectors) to unstaged (4 injectors). The controller cuts the pulse length to = about 1/2 when this happens so the net effect on fuel delivery is very small. = The amount that does change should be tuned out by using Mode 6 PRIOR to any = MAP table tuning. See the previous message on this subject. When in doubt, RTFM! One caveat. The manual has been updated many times over the years. If you don't have a current edition, feel free to ask = for a MS Word copy of the manual via email but be sure your controller has = been updated to match the documentation. Tracy =20 =20 =20 ------=_NextPart_000_001C_01C990EA.AA2CA790 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Tracy,

 

I have always wondered why so many = people seem to have trouble with staging, myself included.  My setup uses = all four injectors of the same part number and the flow rates and dynamic = ranges are very well matched as demonstrated on a flow bench.  =

 

As you know, I am in the process of retuning my system after an EC2 upgrade.  When looking at data = logged from the EC2 at less than 1 second intervals, there appears to be an = inconsistency in the manifold pressure corresponding to the staging address and the = manifold pressure the EC2 reports when staging actually takes place.  In my = case staging will take place with the manifold pressure reported by the EC2 = up to 4 In Hg less than that corresponding to the staging address.  So far = I have not seen the system stage at the manifold pressure corresponding to the = staging address.

 

Is it possible that the EC2 is = actually staging at a lower manifold pressure than that set in the staging address, using = the mixture correction table value at that lower address, and when the manifold = pressure rises sufficiently, the correct correction table addresses are used = again?  With my mixture correction table, a significant increase in table values is = required just above the staging threshold.  If the above were happening, the mixture would go very lean when the EC2 staged and used the values in = the correction table lower than the staging address.  This is what I = see on the O2 sensors when there is a problem staging.

 

I hadn’t tried to change mode = 6 settings since I am sure my injectors are very well matched and the = manual indicates that in this case mode 6 changes shouldn’t be = needed.  Your message brings up the thought that if the above is happening, one may be = able to use mode 6 to obtain a mixture correction table where there is no or = very little change in table values for addresses in the region corresponding = to the staging point and a couple of inches of manifold pressure below = that.  Then it wouldn’t matter exactly what manifold pressure the EC2 = actually staged at or the actual correction table value used since the mixture = would still be close to correct.  Mode 1 or 9 may still be able to obtain = correct mixtures outside this region.  Is it possible that those who have = no staging issues have stumbled on this type of mixture correction table accidentally?

 

Crawling back into my hole to = continue to RTFM.

 

Steve Boese =    

 

 

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Tuesday, February = 17, 2009 9:30 AM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Second flight

 

Again, it is very important to understand what is happening.  Without this understanding, a builder is working in the dark.

 Fuel delivery is not doubled when the EC2/3 goes from staged (2 injectors) to unstaged (4 injectors).  The controller cuts the = pulse length to about 1/2 when this happens so the net effect on fuel delivery = is very small.  The amount that does change should be tuned out by = using Mode 6 PRIOR to any MAP table tuning.  See the previous message on this subject.

When in doubt, RTFM!  One caveat. The manual has been updated many = times over the years.  If you don't have a current edition, feel free to = ask for a MS Word copy of the manual via email but be sure your controller has = been updated to match the documentation.

Tracy

 

 

 

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