Return-Path: Received: from mallard.mail.pas.earthlink.net ([207.217.120.48] verified) by logan.com (CommuniGate Pro SMTP 4.2b1) with ESMTP id 3140260 for flyrotary@lancaironline.net; Thu, 01 Apr 2004 07:47:04 -0500 Received: from h-68-164-228-8.chcgilgm.dynamic.covad.net ([68.164.228.8] helo=Barry) by mallard.mail.pas.earthlink.net with smtp (Exim 3.33 #1) id 1B91b5-0003g2-00 for flyrotary@lancaironline.net; Thu, 01 Apr 2004 04:47:03 -0800 Message-ID: <005601c417e7$69a1eb80$6401a8c0@Barry> From: "Barry Gardner" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: 13B Intake Manifolds Date: Thu, 1 Apr 2004 06:46:54 -0600 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0053_01C417B5.1EB98290" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 This is a multi-part message in MIME format. ------=_NextPart_000_0053_01C417B5.1EB98290 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 13B Intake ManifoldsWith that clue, I think I know my answer. Atkins = must have supplied you with the 850cc injectors that powered the 85-86 = GSL-SE 13B. In that iteration of the car, Mazda used those.=20 In 1986-87, Mazda switched to using four 460cc injectors in the = naturally-aspirated car and using four 550cc injectors in the Turbo II. = While those had more potential for overall fuel flow, it meant that they = had them staged. I'm not positive of the exact RPM changeover to using = all four but my recollection is that it was 3800 rpm. My Turbo II has a = little hicup in acceleration when it passes through that point and the = factory wrestled with getting that right--something usually chalked up a = bad ground. They worked fine when new but sometimes developed the hicup = when they got a little older and the ground was a tad less reliable. How many horsepower did you intend to get out of your turbocharged rig? = I think you're fine but might be near the limit at a little over 200 HP. = Any projections? You've got 1700cc/min. The naturally-aspirated car ran four times 460cc = or 1840cc. The 87 Turbo II ran four times 550cc or 2200cc.=20 Somewhere around here I've got a book on fuel injection that figures out = the conversion for fuel adequacy (and helps with the metric/min to = pounds/hr conversion). I think you also have to use an 80% or 85% duty = cycle or else the injector is basically open all the time, which for = some reason isn't recommended. The reason I asked about this is that those 850cc injectors were some of = the biggest in the auto world, at least at the time and might be still. = Other manufacturers used multiple injectors that corresponded to the = number of cylinders, so typically you find hot-rodded Mustangs, etc., = using eight, which of course could be smaller individually to sum to an = even bigger whole. When I saw your two injectors, the reason I wrote was = because I thought you might have discovered some even bigger ones than = the GSL-SE. Rumor was that Mazda had a hard time getting the big ones like you've = got to run smoothly at the bottom end, which is why they switched in the = next iteration of the car to four injectors--but remember they were = looking for a smooth 750 RPM idle speed. Aviators need neither that = smoothness nor an idle that low. Anyhow, I was just surprised to see the two big MONGO injectors feeding = all that airflow. I think the Mazda 850cc injectors might be on that = table that Paul Lamar reprints from time to time, if you're interested = in working out the lbs/hr and then BSFC conversion to re-confirm the top = end of your fuel flow. Barry Gardner Wheaton, IL ----- Original Message -----=20 From: sqpilot@earthlink=20 To: Rotary motors in aircraft=20 Sent: Wednesday, March 31, 2004 9:28 PM Subject: [FlyRotary] Re: 13B Intake Manifolds I purchased the throttlebody, ECU and programmer from Atkins Rotary. = The throttlebody came with the injectors already installed. Not sure = what the injector flow, model, etc are. I have that info somewhere, but = it will take some searching through a lot of e-mails to find it. Paul = Conner ----- Original Message -----=20 From: Barry Gardner=20 To: Rotary motors in aircraft=20 Sent: Wednesday, March 31, 2004 4:23 PM Subject: [FlyRotary] Re: 13B Intake Manifolds Paul Conner-- I was looking at that picture of your manifold you enclosed. It = seemed like you only had two injectors.=20 If true, what kind of fuel flow are they rated for and what is the = brand/model number? Those must be big--no, MAMMOTH--injectors. Barry Gardner Wheaton, IL ------=_NextPart_000_0053_01C417B5.1EB98290 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable 13B Intake Manifolds
With that clue, I think I know my = answer. Atkins=20 must have supplied you with the 850cc injectors that powered the 85-86 = GSL-SE=20 13B. In that iteration of the car, Mazda used those.
 
In 1986-87, Mazda switched to using = four 460cc=20 injectors in the naturally-aspirated car and using four 550cc injectors = in the=20 Turbo II. While those had more potential for overall fuel flow, it meant = that=20 they had them staged. I'm not positive of the exact RPM changeover to = using all=20 four but my recollection is that it was 3800 rpm. My Turbo II has a = little hicup=20 in acceleration when it passes through that point and the factory = wrestled with=20 getting that right--something usually chalked up a bad ground. They = worked fine=20 when new but sometimes developed the hicup when they got a little older = and the=20 ground was a tad less reliable.
 
How many horsepower did you intend to = get out of=20 your turbocharged rig? I think you're fine but might be near the limit = at a=20 little over 200 HP. Any projections?
 
You've got 1700cc/min. The = naturally-aspirated car=20 ran four times 460cc or 1840cc. The 87 Turbo II ran four times 550cc or = 2200cc.=20
 
Somewhere around here I've got a book = on fuel=20 injection that figures out the conversion for fuel adequacy (and helps = with the=20 metric/min to pounds/hr conversion). I think you also have to use an 80% = or 85%=20 duty cycle or else the injector is basically open all the time, which = for some=20 reason isn't recommended.
 
The reason I asked about this is that = those 850cc=20 injectors were some of the biggest in the auto world, at least at the = time and=20 might be still. Other manufacturers used multiple injectors that = corresponded to=20 the number of cylinders, so typically you find hot-rodded Mustangs, = etc., using=20 eight, which of course could be smaller individually to sum to an even = bigger=20 whole. When I saw your two injectors, the reason I wrote was because I = thought=20 you might have discovered some even bigger ones than the = GSL-SE.
 
Rumor was that Mazda had a hard time = getting the=20 big ones like you've got to run smoothly at the bottom end, which is why = they=20 switched in the next iteration of the car to four injectors--but = remember they=20 were looking for a smooth 750 RPM idle speed. Aviators need neither that = smoothness nor an idle that low.
 
Anyhow, I was just surprised to see the = two big=20 MONGO injectors feeding all that airflow. I think the Mazda 850cc = injectors=20 might be on that table that Paul Lamar reprints from time to time, if = you're=20 interested in working out the lbs/hr and then BSFC conversion to = re-confirm the=20 top end of your fuel flow.
 
Barry Gardner
Wheaton, IL
----- Original Message -----
From:=20 sqpilot@earthlink
Sent: Wednesday, March 31, 2004 = 9:28=20 PM
Subject: [FlyRotary] Re: 13B = Intake=20 Manifolds

I purchased the throttlebody, ECU and = programmer=20 from Atkins Rotary. The throttlebody came with the injectors already=20 installed.  Not sure what the injector flow, model, etc = are.  I have=20 that info somewhere, but it will take some searching through a lot of = e-mails=20 to find it.   Paul Conner
----- Original Message -----
From:=20 Barry Gardner
To: Rotary motors in = aircraft=20
Sent: Wednesday, March 31, = 2004 4:23=20 PM
Subject: [FlyRotary] Re: 13B = Intake=20 Manifolds

Paul Conner--
 
I was looking at that picture of = your manifold=20 you enclosed. It seemed like you only had two injectors. =
 
If true, what kind of fuel flow are = they rated=20 for and what is the brand/model number?  Those must be=20 big--no, MAMMOTH--injectors.
 
Barry Gardner
Wheaton, IL
 
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