X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from EXHUB003-4.exch003intermedia.net ([207.5.74.111] verified) by logan.com (CommuniGate Pro SMTP 5.4c3j) with ESMTPS id 4988756 for flyrotary@lancaironline.net; Thu, 19 May 2011 13:21:44 -0400 Received-SPF: none receiver=logan.com; client-ip=207.5.74.111; envelope-from=jwhaley@datacast.com Received: from EXVMBX003-5.exch003intermedia.net ([207.5.74.45]) by EXHUB003-4.exch003intermedia.net ([207.5.74.111]) with mapi; Thu, 19 May 2011 10:21:07 -0700 From: Jeff Whaley To: "flyrotary@lancaironline.net" Date: Thu, 19 May 2011 10:22:21 -0700 Subject: RE: Engine Tuning Thread-Topic: Engine Tuning Thread-Index: AcwWC7h48sEAcJeqTbaZhuQJUhn7JAAOR4TQ Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Steve, I would say your interpretation of my message was bang-on. However t= o further clarify what I was saying about fuel flow indicators ... once you= have "tuned" the EC2 using whatever method you chose, the only thing that = changes external to the EC2 is injector pulse width. So in theory if your = MCT is a flat line you could plot the injector pulse width Vs rpm and come = up with a graph very similar to what Ed and I have submitted for our MCTs. = These MCTs were derived manually using Mode 1-only after first setting the= post-staged injector flow rate with Mode 3. I'm not saying this is the be= st way but to me at the time it removed the "mystery" of what the EC2 was d= oing with Modes 6 and 2 and thus the MCT is itself a truer representation o= f fuel delivery. BTW, nice software package you have made available at rotarycopilot.com ...= I will at some point download it. Jeff From: "Steven W. Boese" Subject: RE: [FlyRotary] Re: Engine Tuning Date: Thu, 19 May 2011 09:30:53 -0600 To: Rotary motors in aircraft Jeff, One way of reading the controller parameters is described in the following = website: www.rotarycopilot.com/ The software to do this can be downloaded from this site. If you already h= ave a computer, the only cost to do this is the voltage converter for the s= erial connection, the wiring to the controller which may already be install= ed, and the time invested. There is some indication that this data is available from the EM2/3 display= . It may be in hexadecimal format but converting that to decimal would be = straightforward. I don't have an EM2/3 so I am not positive that this is t= he case. I have been flying with a default (flat line at midrange zero) mixture corr= ection table for some time now with good results. The tuning was performed= as you describe. A default mixture correction table has also been used on= my engine test stand with various combinations of different sized primary = and secondary injectors giving equally good results. The values for mode 3, mode 6, the mixture control, and the mixture correct= ion table all appear to be used to calculate an injector pulse width for a = given manifold pressure and appear to be independent and additive. The value at a particular address in the mixture correction table is not a = pulse width, but a value used along with the others to calculate the pulse = width to be used. I am not aware of a readout of the pulse width in use th= at is directly available from the EC or EM equipment and have assembled my = own equipment for this purpose. The pulse width itself tells nothing about fuel delivery. When combined wi= th the injector characteristics, however, it very accurately defines the fu= el delivery. The controller has no initial knowledge of what the injector characteristic= s are or if an injector is even connected to it. This information is suppl= ied by feedback from the person doing the tuning through the adjustments of= the parameters mentioned. In Brian's case, I'm just suggesting that the feedback may have produced pa= rameters that result in long enough pulse widths to cause static injector o= peration at the RPM's he is capable of attaining. That particular combinat= ion of parameters (and many others) would produce static injector operation= regardless of what injector would be connected to the controller. The use= of larger injectors may not have resulted in feedback leading to that comb= ination of parameters, of course. I am not contending that this is actuall= y happening, but that it is possible and easy to verify. I agree that the best way to monitor fuel flow would be through the use of = a fuel flow meter. Preferably one based on a sensor such as a Floscan type= which is independent of the rest of the fuel system, but unfortunately exp= ensive. In the end, the engine will tell the operator if it is happy or no= t and the operator would already know this before looking at the fuel flow = meter. The O2 sensor seems to be more useful in keeping the engine happy. I hope I have interpreted your message correctly and my response is just my= way of looking at things with no claim of absolute certainty. Steve __________ Information from ESET NOD32 Antivirus, version of virus signatur= e database 6135 (20110519) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com This message, and the documents attached hereto, is intended only for the a= ddressee and may contain privileged or confidential information. Any unauth= orized disclosure is strictly prohibited. If you have received this message= in error, please notify us immediately so that we may correct our internal= records. Please then delete the original message. Thank you.