X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-db01.mx.aol.com ([205.188.91.95] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with ESMTP id 5384786 for flyrotary@lancaironline.net; Mon, 06 Feb 2012 11:23:43 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.188.91.95; envelope-from=bktrub@aol.com Received: from mtaomg-da03.r1000.mx.aol.com (mtaomg-da03.r1000.mx.aol.com [172.29.51.139]) by imr-db01.mx.aol.com (8.14.1/8.14.1) with ESMTP id q16GMvDU024352 for ; Mon, 6 Feb 2012 11:22:57 -0500 Received: from core-duc003b.r1000.mail.aol.com (core-duc003.r1000.mail.aol.com [172.29.164.137]) by mtaomg-da03.r1000.mx.aol.com (OMAG/Core Interface) with ESMTP id 25894E0000A0 for ; Mon, 6 Feb 2012 11:22:57 -0500 (EST) References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: Upper end tuning In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: bktrub@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CEB302B85F2CB3_1F0C_7823E_webmail-m021.sysops.aol.com" X-Mailer: AOL Webmail 35412-STANDARD Received: from 50.46.146.205 by webmail-m021.sysops.aol.com (64.12.183.102) with HTTP (WebMailUI); Mon, 06 Feb 2012 11:22:57 -0500 Message-Id: <8CEB302B850E44F-1F0C-1EB0D@webmail-m021.sysops.aol.com> X-Originating-IP: [50.46.146.205] Date: Mon, 6 Feb 2012 11:22:57 -0500 (EST) x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20110426; t=1328545377; bh=YwZ/iHBXiDlWRpJXCo2cJAClRBneOawPDF3iPpR2BgY=; h=From:To:Subject:Message-Id:Date:MIME-Version:Content-Type; b=krRCRBuxWPAPlmM7r9TB5szq6Xeg12/TyfRg25uXngr/JQFuHzWSuS+7eMNV0xwjn k9l7uyIRWL4eah4oIeu5s94MHIOoGAzNx/mNSf+qz2NuReyYBljmk5UwnMMDhccdk7 iLzVpMGHQSl+PKqL5AsRWnNXPT2ewWNa5kpfBCXc= X-AOL-SCOLL-SCORE: 0:2:478944192:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d338b4f2ffe616876 This is a multi-part message in MIME format. ----------MB_8CEB302B85F2CB3_1F0C_7823E_webmail-m021.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" My coils are the LS1 coils. I have around 40 hours on the spark plugs, what= with all the ground runs added to the flying. So, a new set of plugs is go= ing in. Fortunately the engine runs well through the rest of the RPM range= , so I feel comforable flying the plane and will be out the next few days t= rying to remedy this issue. Temps are good with the outside air temp around= 50. I haven't had the oil or coolant above 160 while flying, so I should b= e good in the summer months. Right now I partiall blocked the Rad and oil c= ooler. Otherwise, I would have temps in the 130 range for my fluids.=20 Brian Trubee -----Original Message----- From: Ernest Christley To: Rotary motors in aircraft Sent: Mon, Feb 6, 2012 7:39 am Subject: [FlyRotary] Re: Upper end tuning What coils are you using? Steve mentioned spark plugs, but there was a oncern on the rx7clu8 mailing list that EDIS coils in a wasted spark etup would saturate in a high RPM/high MP situation. I've not run into hat, but a hard limit like that suggests that the coils might not be ble to keep up with what they are being asked to do. Tracy wrote: Can't make an educated guess from the data given but here's a few questions & comments. Can you clarify what you mean by "precipitous power drop"? Does the power go down at higher MP? (6100 at 22.6" aint bad on a FP prop.=20 What was the airspeed & altitude? EVERYTHING MATTERS!) Is the EGT imbalance only at high power? Are you sure it's not instrumentation error? As Ed asked, what was the result of varying the mixture control at high power?=20 You say that engine is silky smooth below 6100. Does that imply it is rough above 6100? The % power readout of the EM2 is meaningless if the fuel flow function isn't calibrated and you haven't plugged in a realistic value for your engine's max power. Tracy On Sun, Feb 5, 2012 at 10:01 PM, > wrote: I've got just over 20 hours on my plane today, all of the lower- end bugs have been worked out. Right now I'm having power drop off precipitously right at 6100 rpm- 22.6 inches of MP and around 70% power according to the EM2. This is around 130-140 mph IAS. The fuel injection Map shows a smooth graph at that point. I thought that there might be a timing issue so I tried advancing the timing about 2 degrees but that did not change a thing so I set the timing back where it was previously. I am seeing about a 180 f difference on the two rotors- I went to mode four to try to balance out the egts, but I could only effect about a 20 degree change. Rotor 2 consistently shows somewhere above 1800 F, which I tend to question. I'll re-check my calibration. I have had the injectors cleaned and tested so unless one of them got clogged, that should not be an issue. Still, I should pull them and have them re-checked. I may have an issue with the EGT probes themselves. =20 Down below 6100 rpm the engine is smooth as silk, but obviously there is an issue above that . =20 =20 Brian Trubee RV-4 13 BREW =20 - omepage: http://www.flyrotary.com/ rchive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.h= tml ----------MB_8CEB302B85F2CB3_1F0C_7823E_webmail-m021.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="us-ascii"
My coils are the LS1 coils= . I have around 40 hours on the spark plugs, what with all the ground runs = added to the flying. So, a new set of plugs is going in.  Fortunately = the engine runs well through the rest of the RPM range, so I feel comforabl= e flying the plane and will be out the next few days trying to remedy this = issue. Temps are good with the outside air temp around 50. I haven't had th= e oil or coolant above 160 while flying, so I should be good in the summer = months. Right now I partiall blocked the Rad and oil cooler.  Otherwis= e, I would have temps in the 130 range for my fluids.
 
Brian Trubee
 



 
= -----Original Message-----
From: Ernest Christley <echristley@nc.rr.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Mon, Feb 6, 2012 7:39 am
Subject: [FlyRotary] Re: Upper end tuning

What c=
oils are you using?  Steve mentioned spark plugs, but there was a
concern on the rx7clu8 mailing list that EDIS coils in a wasted spark
setup would saturate in a high RPM/high MP situation.  I've not run into
that, but a hard limit like that suggests that the coils might not be
able to keep up with what they are being asked to do.

Tracy wrote:
> Can't make an educated guess from the data given but here's a few
> questions & comments.
>
> Can you clarify what you mean by "precipitous power drop"?  Does the
> power go down at higher MP?  (6100 at 22.6" aint bad on a FP prop.=20
> What was the airspeed & altitude?  EVERYTHING MATTERS!)
>
> Is the EGT imbalance only at high power?  Are you sure it's not
> instrumentation error?
>
> As Ed asked, what was the result of varying the mixture control at
> high power?=20
>
> You say that engine is silky smooth below 6100.  Does that imply it is
> rough above 6100?
>
> The % power readout of the EM2 is meaningless if the fuel flow
> function isn't calibrated and you haven't plugged in a realistic value
> for your engine's max power.
>
> Tracy
>
>
> On Sun, Feb 5, 2012 at 10:01 PM, <bktrub@aol.com
> <mailto:bktrub@aol.com>&g=
t; wrote:
>
>     I've got just over 20 hours on my plane today, all of the lower-
>     end bugs have been worked out. Right now I'm having power drop off
>     precipitously right at 6100 rpm- 22.6 inches of MP and around 70%
>     power according to the EM2. This is around 130-140 mph IAS. The
>     fuel injection Map shows a smooth graph at that point. I thought
>     that there might be a timing issue so I tried advancing the timing
>     about 2 degrees but that did not change a thing so I set the
>     timing back where it was previously. I am seeing about a 180 f
>     difference on the two rotors- I went to mode four to try to
>     balance out the egts, but I could only effect about a 20 degree
>     change. Rotor 2 consistently shows somewhere above 1800 F, which I
>     tend to question. I'll re-check my calibration.   I have had the
>     injectors cleaned and tested so unless one of them got clogged,
>     that should not be an issue. Still, I should pull them and have
>     them re-checked. I may have an issue with the EGT probes themselve=
s.
>     =20
>      Down below 6100 rpm the engine is smooth as silk, but obviously
>     there is an issue above that .
>     =20
>     =20
>     Brian Trubee
>     RV-4  13 BREW
>     =20
>
>


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