X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp02.syd.iprimus.net.au ([210.50.76.196] verified) by logan.com (CommuniGate Pro SMTP 4.3.4) with ESMTP id 1008428 for flyrotary@lancaironline.net; Mon, 20 Jun 2005 22:17:05 -0400 Received-SPF: pass receiver=logan.com; client-ip=210.50.76.196; envelope-from=daval@iprimus.com.au Received: from [192.168.1.8] (211.26.28.186) by smtp02.syd.iprimus.net.au (7.2.060.1) id 42A0B1C100562497 for flyrotary@lancaironline.net; Tue, 21 Jun 2005 12:16:14 +1000 Mime-Version: 1.0 (Apple Message framework v622) In-Reply-To: References: Content-Type: multipart/alternative; boundary=Apple-Mail-38--720946892 Message-Id: From: david mccandless Subject: Re: [FlyRotary] Re: Fuel Injector Position (was Re: Date: Tue, 21 Jun 2005 10:16:13 +0800 To: "Rotary motors in aircraft" X-Mailer: Apple Mail (2.622) --Apple-Mail-38--720946892 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; format=flowed Hi Jim in the PL dyno example that I was referring to, the injectors are just downstream of the bell mouths, and the TB is placed near the port. BR, Dave McC On 21/06/2005, at 9:59 AM, Jim Sower wrote: > > > Dale Rogers wrote: >> Jim, >> >> I think you skimmed over an important qualification of >> Dave's comment: >> >> >>>> ... The worry to me here is that with the >>>> TB at the other end of the runner,ie close to the port, >>>> >> which exactly fills this part of your analysis: Really? Are his >> injectors UPstream from the throttle body? That's what I said caused >> carb ice. I understood him to say that his injectors were near (but >> DOWNstream from) his throttle body. >>> .. I think carb ice is pretty much always associated with >>> fuel sprayed into a venturi, and the injectors in our application are >>> always downstream of the "venturi" formed by the partially open >>> throttle. >>> >> Dale R. >> (the world needs more Lerts ...) >> >> >>> From: Jim Sower >>> Date: 2005/06/20 Mon PM 09:18:54 EDT >>> To: "Rotary motors in aircraft" >>> Subject: [FlyRotary] Re: Fuel Injector Position (was Re: >>> Makingprogress on Chris n Dave's Velocity Engine) >>> >>> But wouldn't that be true of ANY injectors placed a significant >>> distance >>> from the block? I think carb ice is pretty much always associated >>> with >>> fuel sprayed into a venturi, and the injectors in our application are >>> always downstream of the "venturi" formed by the partially open >>> throttle. >>> I wouldn't worry ... Jim S. >>> >>> david mccandless wrote: >>> >>> >>>> On PL's recent PP dyno run, he stated that with the injectors >>>> placed near the entry of the runners, there was considerable >>>> evaporative cooling taking place and as the tubes were running >>>> very cold VE should be good. The worry to me here is that with >>>> the >>>> TB at the other end of the runner,ie close to the port, there >>>> is a >>>> real risk of ice build up on the throttle body butterfly. The >>>> old >>>> bugbear of carb ice is back. FWIW, Dave McC >>>> >>>> >>>> since the >>>> >>>> ----- Original Message ----- *From:* Jerry Hey >>>> >>>> based on Paul Lamar's current p port testing there is no >>>> problem with placing the injectors at the far end of the >>>> runners. This is also backed up by an article on the >>>> internet >>>> (How to Fabricate an Intake Manifold) The idle issue is not >>>> with injector location but rather with butterfly location. >>>> >>>> >>>> >>>>> Homepage: http://www.flyrotary.com/ >>>>> Archive: http://lancaironline.net/lists/flyrotary/List.html >>>>> >> >> >>>> Homepage: http://www.flyrotary.com/ >>>> Archive: http://lancaironline.net/lists/flyrotary/List.html >>>> >> >> > >> Homepage: http://www.flyrotary.com/ > > >> Archive: http://lancaironline.net/lists/flyrotary/List.html --Apple-Mail-38--720946892 Content-Transfer-Encoding: 7bit Content-Type: text/enriched; charset=US-ASCII Hi Jim in the PL dyno example that I was referring to, the injectors are just downstream of the bell mouths, and the TB is placed near the port. BR, Dave McC On 21/06/2005, at 9:59 AM, Jim Sower wrote: Dale Rogers wrote: Jim, I think you skimmed over an important qualification of Dave's comment: ... The worry to me here is that with the TB at the other end of the runner,ie close to the port, which exactly fills this part of your analysis: 0000,0000,9998Really? Are his injectors UPstream from the throttle body? That's what I said caused carb ice. I understood him to say that his injectors were near (but DOWNstream from) his throttle body. .. I think carb ice is pretty much always associated with 9998,0000,0000fuel sprayed into a venturi, and the injectors in our application are always downstream of the "venturi" formed by the partially open throttle. Dale R. (the world needs more Lerts ...) From: Jim Sower 0000,0000,EEED< Date: 2005/06/20 Mon PM 09:18:54 EDT To: "Rotary motors in aircraft" 0000,0000,EEED< Subject: [FlyRotary] Re: Fuel Injector Position (was Re: Makingprogress on Chris n Dave's Velocity Engine) But wouldn't that be true of ANY injectors placed a significant distance from the block? I think carb ice is pretty much always associated with fuel sprayed into a venturi, and the injectors in our application are always downstream of the "venturi" formed by the partially open throttle. I wouldn't worry ... Jim S. david mccandless wrote: On PL's recent PP dyno run, he stated that with the injectors placed near the entry of the runners, there was considerable evaporative cooling taking place and as the tubes were running very cold VE should be good. The worry to me here is that with the TB at the other end of the runner,ie close to the port, there is a real risk of ice build up on the throttle body butterfly. The old bugbear of carb ice is back. FWIW, Dave McC since the ----- Original Message ----- *From:* Jerry Hey based on Paul Lamar's current p port testing there is no problem with placing the injectors at the far end of the runners. This is also backed up by an article on the internet (How to Fabricate an Intake Manifold) The idle issue is not with injector location but rather with butterfly location. Homepage: 0000,0000,EEEDhttp://www.flyrotary.com/ Archive: 0000,0000,EEEDhttp://lancaironline.net/lists/flyrotary/List.html Homepage: 0000,0000,EEEDhttp://www.flyrotary.com/ Archive: 0000,0000,EEEDhttp://lancaironline.net/lists/flyrotary/List.html >> Homepage: http://www.flyrotary.com/ >> Archive: http://lancaironline.net/lists/flyrotary/List.html --Apple-Mail-38--720946892--