X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail01.syd.optusnet.com.au ([211.29.132.182] verified) by logan.com (CommuniGate Pro SMTP 5.1.12) with ESMTPS id 2336629 for flyrotary@lancaironline.net; Mon, 17 Sep 2007 21:20:16 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.182; envelope-from=lendich@optusnet.com.au Received: from george (d220-237-213-202.dsl.nsw.optusnet.com.au [220.237.213.202]) by mail01.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l8I1JXeN023170 for ; Tue, 18 Sep 2007 11:19:34 +1000 Message-ID: <002501c7f991$fc1e0b30$cad5eddc@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] One for the guys that don't give up Date: Tue, 18 Sep 2007 11:19:38 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0022_01C7F9E5.CCF12050" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0022_01C7F9E5.CCF12050 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Al, I can't remember exactly, but I believe PL's problem with running the = slide throttle was because he had the Vacuum pick-up tube on the runners = to the engine. The reason Tracy gave for the ECU not working was because = of that set-up, as his Vacuum pick -up is at the Plenum - something to = do with fluctuations within the tube, whereby the plenum was static or = less successful to wild fluctuations. George ( down under) I don't seldom give up on a problem, but I came awfully close this = time. Mark OK; Mark; (or anybody). Since we both have 20Bs, and both use the EC2 = controller, maybe you have a clue for this one. I've brought this up = here before, but no solution. I have all the latest updates on the EC2, and I have double checked = the static timing set at 35o BTDC. From that point on the EC2 is = handling the timing curve with rpm and MAP. At lower power levels, disabling the leading ignition clearly has a = larger effect than disabling the trailing - as one would expect. At = somewhere around 18" MAP, (don't know right now what rpm that is, maybe = close to 4000) the effect is about equal when disabling either set. At = higher power levels, there is a larger effect of disabling the trailing = than the leading. That troubles me. I think the leading should always = have a greater effect. It makes me wonder about the timing; or if = something else is wrong.=20 I have in the past tried varying the timing 2 or 3 steps while at = power, but couldn't discern a change in rpm greater than the normal = variation in the readout. Tracy sent me the XL spreadsheet with the = timing curve data, but I haven't yet figured a safe way of checking it = with that prop spinning close by. Does your installation exhibit the same behavior? Is there some = explanation for this? What test should I perform? One thing that occurs to me is that Tracy measures MAP out before the = runners. I measure MAP at the manifold, downstream from intake plenum = and three short runners and the 3-barrel TWM throttle body. At WOT my = MAP is not atmospheric pressure - it is maybe 2-3" HG less. I can't = quite see how that is an issue; but maybe someone else with a TWM TB = setup with the MAP port downstream would know. Other than that I'm very pleased with the new mixture correction table = setup for the 20B. Much less tuning and seamless transistion between = tables and through the stage point. Probably the pulse clamping and = injector isolation diodes are part of that. -------------------------------------------------------------------------= ----- No virus found in this incoming message. Checked by AVG Free Edition.=20 Version: 7.5.487 / Virus Database: 269.13.22/1013 - Release Date: = 17/09/2007 1:29 PM ------=_NextPart_000_0022_01C7F9E5.CCF12050 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Al,
I can't remember exactly, but I believe = PL's=20 problem with running the slide throttle was because he had = the Vacuum=20 pick-up tube on the runners to the engine. The reason Tracy gave for the = ECU not=20 working was because of that set-up, as his Vacuum pick -up = is at the=20 Plenum - something to do with fluctuations within the tube, whereby the = plenum=20 was static or less successful to wild fluctuations.
George ( down under)


I don't seldom = give up on a=20 problem, but I came awfully close this = time.

Mark

OK;=20 Mark; (or anybody).  Since we both have 20Bs, and both use the = EC2=20 controller, maybe you have a clue for this one. I=92ve brought this up = here=20 before, but no solution.

I have = all the=20 latest updates on the EC2, and I have double checked the static timing = set at=20 35o BTDC.  From that point on the EC2 is handling the = timing=20 curve with rpm and MAP.

At lower = power=20 levels, disabling the leading ignition clearly has a larger effect = than=20 disabling the trailing =96 as one would expect.  At somewhere = around 18=94=20 MAP, (don=92t know right now what rpm that is, maybe close to 4000) = the effect=20 is about equal when disabling either set.  At higher power = levels, there=20 is a larger effect of disabling the trailing than the leading.  = That=20 troubles me.  I think the leading should always have a greater=20 effect.  It makes me wonder about the timing; or if something = else is=20 wrong.

I have in = the past=20 tried varying the timing 2 or 3 steps while at power, but couldn=92t = discern a=20 change in rpm greater than the normal variation in the readout. =20 Tracy sent me = the XL=20 spreadsheet with the timing curve data, but I haven=92t yet figured a = safe way=20 of checking it with that prop spinning close by.

Does your = installation exhibit the same = behavior? =20 Is there some explanation for this?  What test should I=20 perform?

One thing = that=20 occurs to me is that Tracy measures = MAP out=20 before the runners.  I measure MAP at the manifold, downstream = from=20 intake plenum and three short runners and the 3-barrel TWM throttle=20 body.  At WOT my MAP is not atmospheric pressure =96 it is maybe = 2-3=94 HG=20 less.  I can=92t quite see how that is an issue; but maybe = someone else=20 with a TWM TB setup with the MAP port downstream would = know.

 

Other = than that I=92m=20 very pleased with the new mixture correction table setup for the = 20B. =20 Much less tuning and seamless transistion between tables and through = the stage=20 point.  Probably the pulse clamping and injector isolation diodes = are=20 part of that.

No virus found in this incoming message.
Checked by AVG Free = Edition.
Version: 7.5.487 / Virus Database: 269.13.22/1013 - = Release Date:=20 17/09/2007 1:29 PM
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