X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from mail17.syd.optusnet.com.au ([211.29.132.198] verified) by logan.com (CommuniGate Pro SMTP 5.1.7) with ESMTPS id 1914382 for flyrotary@lancaironline.net; Sun, 11 Mar 2007 03:07:36 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.198; envelope-from=lendich@optusnet.com.au Received: from george (d220-236-54-58.dsl.nsw.optusnet.com.au [220.236.54.58]) by mail17.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l2B76dcI020448 for ; Sun, 11 Mar 2007 18:06:41 +1100 Message-ID: <002301c763ab$d269e060$3a36ecdc@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: The truth??? / Injector flow rate mystery solved Date: Sun, 11 Mar 2007 17:06:41 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0020_01C763FF.A33F6680" 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_0020_01C763FF.A33F6680 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MessageThanks for confirming that Ed! If Tracy's efforts to 'further' control the idle are successful, it must = be a good thing for FI coupled with PP. George ( down under) That's what it boils down to, George. After the open pulse terminates = and the injector should close in less than a millisecond, a diode causes = the injectors' magnetic field to hold open the pintel up to several = milliseconds longer than it should. Therefore the mixture actually ends = up richer than the EC2 intended. =20 Now, what is not clear to me, is if you tune using an Air/Fuel Ratio = indicator and then program that value into the EC2 via the program mode = does that compensate for the longer open period by making the pulse = shorter until you get the A/F mixture you want. I suspect that it does = at least to some extent. =20 About the only place you would ever really notice it is at idle - = because at higher rpms - the extra fuel just burns on through - but at = idle more fuel can make a big difference as there is so little air to = begin with in the manifold. It sounds like the "hold" period is not constant therefore, one = correction factor won't work for all the different injector pulsating = duration. But, Tracy will develop a fix for sure. Ed ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Saturday, March 10, 2007 3:48 PM Subject: [FlyRotary] Re: The truth??? / Injector flow rate mystery = solved Is Tracy saying that the injector stays open longer - putting in = more fuel and making the inlet charge richer? George ( down under) Still refining the exact numbers but here is the basic cause. The diode clamp on the injector drivers (in EC2) serves 3 = purposes. It limits the inductive flyback voltage to protect the driver = transistor. It recovers some of the energy used to open the injector = thus reducing the current consumption of the system. It eliminates = arcing at the A/B injector switching relay that can cause noise problems = with the processor chips. Unknown to me until recently, it also significantly increases the = closing time of the injector after the driver pulse ends. I thought the = delay would be negligible. The actual delay depends on several factors = but may be as much as 5 ms (!) Ed will know what a big deal this is. = The factors that go into this and how much it is magnified by the diode = clamp is still under investigation. The good news is that there is a very simple fix. (Note, Do NOT = go out and remove the diode clamps! That isn't the fix! Tracy ----- Original Message -----=20 From: Ed Anderson=20 To: Rotary motors in aircraft=20 Sent: Friday, March 09, 2007 7:13 AM Subject: [FlyRotary] Re: The truth??? / Injector flow rate = mystery solved I certainly don't know, Rusty. Like I said the only thing that = Tracy and I could conclude was that Mazda was under-rating their = injectors - I wondered whether it might have something to do with the = way an engine is taxed in Japan. In any case, Tracy is clearly ignoring our pleas for more = information - poor guy is undoubtedly working furiously getting orders = completed before Sun & Fun. But, he really shouldn't tease like that = {:>) Yes, I understand what you mean about measured flow rates - I = suspect there is something subtle about this matter. Perhaps the = current profile used to open the injectors plays some role in this as = Tracy indicated he was working on a Fix. Perhaps a two stage or = progressive flow rate profile - opens and provides normal flow for = typical automobile usage but, when wide open (like ours are at cruise) = perhaps the flow rate is more. Who knows - Tracy Crook that's who. Ed ----- Original Message -----=20 From: Russell Duffy=20 To: Rotary motors in aircraft=20 Sent: Friday, March 09, 2007 12:19 AM Subject: [FlyRotary] Re: The truth??? / Injector flow rate = mystery solved Tracy and I have been discussing this injector flow rate = anomaly for years - =20 For some reason, I was certain that the Mazda injectors flowed = more than they were rated for, but after sifting through some old logs, = that's not true for all Mazda injectors. I sent 4 slightly used 550's = to RC Engineering, and they tested them at 547, 549, 551, and 551. If = that ain't 550, I don't know what is :-) =20 I guess I'm baffled now. Does Mazda operate them at 5 volts = or something, rather than 12V? That would slow down the response time. = =20 Hey the HKS is a good little engine in my opinion - not as = good as a light weight rotary (which we don't have yet - Richard! get a = move on {:>)), but it'll get you flying again.=20 Thanks for the comments. It can't hurt much to try it, = because I've already got people who want to buy it if it doesn't work = out. Still, it's as much trouble to install as the rotary, so it really = comes down to a weight issue, and perhaps whether I'll ever get my = redrive from Autoflight... =20 Rusty ------=_NextPart_000_0020_01C763FF.A33F6680 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Message
Thanks for confirming that Ed!
If Tracy's efforts to 'further' control the idle = are=20 successful, it must be a good thing for FI coupled with = PP.
George ( down under)
That's what it boils down to, = George.  After=20 the open pulse terminates and the injector should close in less than a = millisecond, a diode causes the injectors'  magnetic field to = hold open=20 the pintel up to several milliseconds longer than it should.  = Therefore=20 the mixture actually ends up richer than the EC2 intended.  =
 
Now, what is not clear to me, is if = you tune=20 using an Air/Fuel Ratio indicator and then program that value into the = EC2 via=20 the program mode does that compensate for the longer open period by = making the=20 pulse shorter until you get the A/F mixture you want.  I suspect = that it=20 does at least to some extent. 
 
About the only place you would ever = really notice=20 it is at idle - because at higher rpms - the extra fuel just burns on = through=20 - but at idle more fuel can make a big difference as there is so = little air to=20 begin with in the manifold.
 
It sounds like the "hold" period is = not constant=20 therefore, one correction factor won't work for all the different = injector=20 pulsating duration.
 
But, Tracy will develop a fix for=20 sure.
 
Ed
----- Original Message -----
From:=20 George Lendich
To: Rotary motors in = aircraft=20
Sent: Saturday, March 10, = 2007 3:48=20 PM
Subject: [FlyRotary] Re: The = truth??? /=20 Injector flow rate mystery solved

Is Tracy saying that the injector stays open = longer -=20 putting in more fuel and making the inlet charge = richer?
George ( down under)
Still refining the exact numbers but here is the basic = cause.
 
The diode clamp on the injector drivers (in EC2) serves 3=20 purposes.  It limits the inductive flyback voltage to protect = the=20 driver transistor.  It recovers some of the energy used to = open the=20 injector thus reducing the current consumption of the = system.  It=20 eliminates arcing at the A/B injector switching relay that can = cause noise=20 problems with the processor chips.
 
Unknown to me until recently, it also significantly increases = the=20 closing time of the injector after the driver pulse ends.  I = thought=20 the delay would be negligible.  The actual delay depends on = several=20 factors but may be as much as 5 ms (!)  Ed will know what a = big deal=20 this is.  The factors that go into this and how much it is = magnified=20 by the diode clamp is still under investigation.
 
The good news is that there is a very simple fix.  = (Note, Do NOT=20 go out and remove the diode clamps! That isn't the fix!
 
Tracy
----- Original Message ----- =
From: Ed Anderson
To: Rotary motors in = aircraft=20
Sent: Friday, March 09, = 2007 7:13=20 AM
Subject: [FlyRotary] Re: = The=20 truth??? / Injector flow rate mystery solved

I certainly don't know, = Rusty.  Like I=20 said the only thing that Tracy and I could conclude was that = Mazda was=20 under-rating their  injectors - I wondered whether it might = have=20 something to do with the way an engine is taxed in = Japan.
 
In any case, Tracy is clearly = ignoring our=20 pleas for more information - poor guy is undoubtedly working = furiously=20 getting orders completed before Sun & Fun.  But, he = really=20 shouldn't tease like that {:>)
 
Yes, I understand what you mean = about=20 measured flow rates - I suspect there is something subtle about = this=20 matter.  Perhaps the current profile used to open the = injectors=20 plays some role in this as Tracy indicated he was working on a=20 Fix.  Perhaps a two stage or progressive flow rate profile = - opens=20 and provides normal flow for typical automobile usage but, when = wide=20 open (like ours are at cruise) perhaps the flow rate is = more.  Who=20 knows - Tracy Crook that's who.
 
Ed
----- Original Message ----- =
From:=20 Russell Duffy
To: Rotary motors in=20 aircraft
Sent: Friday, March 09, = 2007=20 12:19 AM
Subject: [FlyRotary] = Re: The=20 truth??? / Injector flow rate mystery solved

Tracy and I have been = discussing=20 this injector flow rate anomaly for years -  
 
For some reason, I was certain that = the Mazda=20 injectors flowed more than they were rated for, but after = sifting=20 through some old logs, that's not true for all Mazda=20 injectors.   I sent 4 slightly used 550's to=20 RC Engineering, and they tested them at 547, 549, 551, = and=20 551.  If that ain't 550, I don't know what is=20 :-)  
 
I guess I'm baffled now.  Does = Mazda=20 operate them at 5 volts or something, rather than 12V?  = That=20 would slow down the response=20 time.   
 
 
Hey the HKS is a good = little engine=20 in my opinion - not as good as a light weight rotary (which we = don't=20 have yet - Richard! get a move on {:>)), but it'll get = you =20 flying again. 
 
Thanks for = the=20 comments.  It can't hurt much to try it, because = I've=20 already got people who want to buy it if it doesn't work = out. =20 Still, it's as much trouble to install as the rotary, so it = really=20 comes down to a weight issue, and perhaps whether I'll ever = get my=20 redrive from=20 Autoflight...  
 
Rusty
 
=
------=_NextPart_000_0020_01C763FF.A33F6680--