X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 25 Aug 2009 15:49:09 -0400 Message-ID: X-Original-Return-Path: Received: from imr-ma06.mx.aol.com ([64.12.78.142] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3823757 for lml@lancaironline.net; Tue, 25 Aug 2009 07:12:40 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.78.142; envelope-from=Sky2high@aol.com Received: from imo-ma03.mx.aol.com (imo-ma03.mx.aol.com [64.12.78.138]) by imr-ma06.mx.aol.com (8.14.1/8.14.1) with ESMTP id n7PBC0gm007161 for ; Tue, 25 Aug 2009 07:12:00 -0400 Received: from Sky2high@aol.com by imo-ma03.mx.aol.com (mail_out_v42.5.) id q.cf2.5f7f1ceb (39955) for ; Tue, 25 Aug 2009 07:11:56 -0400 (EDT) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Tue, 25 Aug 2009 07:11:55 EDT Subject: Re: [LML] Re: Plenum pressure and Injector performance LOP X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1251198715" X-Mailer: AOL 9.1 sub 5006 X-Spam-Flag:NO X-AOL-SENDER: Sky2high@aol.com -------------------------------1251198715 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Hmmmmmm...... Depends on what objective you are seeking. Ram air to the engine means that your wings are flying at a higher altitude than the one at which your engine is operating. It's free. Grayhawk In a message dated 8/25/2009 5:18:26 A.M. Central Daylight Time, douglasbrunner@earthlink.net writes: You need to pressurize your injectors even if you have a GAMI spread of less than .3 Mike Mahar sells a setup that accomplishes this. Or you can get the "rails" from a TSIO and install them on the IO. One other option that some people have chosen is to just get rid of the ram air. Don Barnes told me at Oshkosh that he got rid of ram air for this very reason and now has 2 air filters (Don correct me if I got it wrong) -----Original Message----- From: Sky2high@aol.com Sent: Aug 24, 2009 10:25 PM To: lml@lancaironline.net Subject: [LML] Re: Plenum pressure and Injector performance LOP Listen up Grasshopper, 1. If the engine is carbureted, you may be out of luck as there is no way to control the F/A ratio in each cylinder. However, you can try step 3 for informational purposes if you have the equipment listed in step 2. 2. You must have an engine monitor and sensors that display (or record) EGT for each Cyl and the fuel flow. 3. Injected engines must perform the GAMI lean test before a "next step." At 75% power (that means at or above 6500 MSL, 7500 if using ram air and KIAS is less than 190, or higher), WOT (necessary to control air distribution when running LOP) . a. Starting sufficiently ROP, lean in small steps (less than .3 gph) and record the EGT for each step for Cyl 1. Continue past peak EGT for that Cyl for about 50F degrees LOP or until ugly roughness. b. repeat "a" for each cylinder. c. Check the gph for each cyl peak EGT. If the spread in .3 gph or less, you are done and you should be able to run LOP 20F, 30F, 40F depending on the spread). 4. If the spread is GT .3 gph, you must fix the A/F ratio. A cheap way to start is to provide equal air pressure to each injector - a wee plenum distribution to each shrouded injector) and repeat the Lean Test. 5. if the lean test shows the proper spread, go fly LOP (less than 75% power)................... 6. If the lean test fails (GT .3 gph spread), consider different sized injector nozzles (either GAMI or others) for the rich/lean cyls. Grayhawk can fly a 320 at 8500 MSL, ROP, 9.5 gph and see 195 KTAS or LOP, 7.5 gph and 186 KTAS (all things being equal) thus eliminating a fuel stop at 3.5 hours cause he could go another hour. 195 x 3.5 = 683, 186 x 4.5 = 837, 837/195 = 4.3 + 1 (re-fuel stop time) = 5.3 Duh! Grayhawk In a message dated 8/24/2009 2:40:57 P.M. Central Daylight Time, Tim@5000feet.com writes: Hey guys, I am remembering a long time ago reading about how the air pressure surrounding the injector can affect how well the injector works. If I'm not mistaken, turbocharged engines even use some pressure manifold around the injector to accommodate for the increased Manifold Pressure. What gets me curious is that I'm having a discussion with some folks right now who are all having problems running Lean of Peak and their engines stumble before they get to peak EGT. Between the group, there are a variety of ignitions such as 2 mags or 1 lightspeed and one mag, and varieties such as 8.5:1, 9:1, and 10:1 compression ratios, but the one constant is that they all have what is purported to be a more effective cowl... the Sam James cowl with a plenum. So I'm wondering if the knowledge base some of you have would provide any insight to the issue. I originally was worried that the 10:1 pistons might make LOP operation harder to accomplish, but perhaps there is just too much air pressure on the outside of the injector? The cowl is known to often have too little exit area, so it could be that the pressure differential is even too high between the top and bottom half of the cowl. Any insight you can give? Thanks, Tim -- For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html ____________________________________ -- For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html -------------------------------1251198715 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable
Hmmmmmm......
 
Depends on what objective you are seeking.  Ram air to the engin= e=20 means that your wings are flying at a higher altitude than the one at=20 which your engine is operating.  It's free.
 
Grayhawk
 
In a message dated 8/25/2009 5:18:26 A.M. Central Daylight Time,=20 douglasbrunner@earthlink.net writes:
You need=20 to pressurize your injectors even if you have a GAMI spread of less than= =20 .3

Mike Mahar sells a setup that accomplishes this.  Or you= can=20 get the "rails" from a TSIO and install them on the IO.

One other= =20 option that some people have chosen is to just get rid of the ram air.&n= bsp;=20 Don Barnes told me at Oshkosh that he got rid of ram air for this
ver= y=20 reason and now has 2 air filters (Don correct me if I got it=20 wrong)




-----Original=20 Message-----
From: Sky2high@aol.com
Sent: Aug 24, 2009 10:25= PM=20
To: lml@lancaironline.net
Subject: [LML] Re: Plenum pressure= and=20 Injector performance LOP

= =
Listen up Grasshopper,
 
1.  If the engine is carbureted, you may be out of= luck=20 as there is no way to control the F/A ratio in each cylinder.  Ho= wever,=20 you can try step 3 for informational purposes if you have the equipmen= t=20 listed in step 2. 
 
2. You must have an engine monitor and sensors that display (or= record)=20 EGT for each Cyl and the fuel flow.
 
3.  Injected engines must perform the GAMI lean test before= a=20 "next step."  At 75% power (that means at or above 6500 MSL, 7500= if=20 using ram air and KIAS is less than 190, or higher), WOT (necessary to= =20 control air distribution when running LOP) . 
    a. Starting sufficiently ROP, lean in sma= ll=20 steps (less than .3 gph) and record the EGT for each step for Cyl 1.&n= bsp;=20 Continue past peak EGT for that Cyl for about 50F degrees LOP or until= ugly=20 roughness.
    b. repeat "a" for each cylinder.
    c. Check the gph for each cyl peak EGT.&n= bsp;=20 If the spread in .3 gph or less, you are done and you should be able= to run=20 LOP 20F, 30F, 40F depending on the spread).
 
4.  If the spread is GT .3 gph,  you must fix the A/F= =20 ratio.  A cheap way to start is to provide equal air pressure to= each=20 injector - a wee plenum distribution to each shrouded injector) and re= peat=20 the Lean Test.
 
5.  if the lean test shows the proper spread, go fly LOP (le= ss=20 than 75% power)...................
 
6. If the lean test fails (GT .3 gph spread), consider different= sized=20 injector nozzles (either GAMI or others) for the rich/lean cyls.
 
Grayhawk can fly a 320 at 8500 MSL, ROP, 9.5 gph and se= e 195=20 KTAS or LOP, 7.5 gph and 186 KTAS (all things being equal) thus elimin= ating=20 a fuel stop at 3.5 hours cause he could go another hour. 195 x 3.5 =3D= 683,=20 186 x 4.5 =3D 837, 837/195 =3D 4.3 + 1 (re-fuel stop time) =3D 5.3&nbs= p;=20 Duh!
 
Grayhawk
 
In a message dated 8/24/2009 2:40:57 P.M. Central Daylight Time,= =20 Tim@5000feet.com writes:
Hey=20 guys, I am remembering a long time ago reading about
how the air= =20 pressure surrounding the injector can affect how
well the injecto= r=20 works.  If I'm not mistaken, turbocharged
engines even use= some=20 pressure manifold around the injector
to accommodate for the incr= eased=20 Manifold Pressure.

What gets me curious is that I'm having a= =20 discussion with some
folks right now who are all having problems= =20 running Lean of Peak
and their engines stumble before they get to= peak=20 EGT. Between
the group, there are a variety of ignitions such as= 2=20 mags
or 1 lightspeed and one mag, and varieties such as 8.5:1,9:1,=20 and 10:1 compression ratios, but the one constant is that
they al= l have=20 what is purported to be a more effective cowl...
the Sam James co= wl=20 with a plenum.  So I'm wondering if the
knowledge base some= of you=20 have would provide any insight
to the issue. I originally was wor= ried=20 that the 10:1 pistons
might make LOP operation harder to accompli= sh,=20 but perhaps
there is just too much air pressure on the outside of= =20 the
injector?  The cowl is known to often have too little=20 exit
area, so it could be that the pressure differential is
ev= en too=20 high between the top and bottom half of the
cowl.

Any insi= ght=20 you can give?
Thanks,
Tim

--
For archives and unsub= =20 http://mail.lancaironline.net:81/lists/lml/List.html

--

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