Mailing List flyrotary@lancaironline.net Message #33766
From: Joe Ewen <jewen@comporium.net>
Subject: Re: [FlyRotary] Fw: Constant Pressure Differential??
Date: Wed, 27 Sep 2006 08:19:43 -0400
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Ed,
 
Thanks, this is useful info.  If you decide to change your fuel regulator, you will have to retune your EC2 (assuming you are using a EC2.)  I have written a program (would still consider it Alpha) that you can see the fuel map tables and write digital values to each of the array elements with a PC.  I would be happy to trade use of the program for your looking over my 20B installation so far.  In case you don't recall, I am located near KLKR.  Also if you go with an Aeromotive regulator, it does not come with the AN fittings, they are the o-ring type.  I am using Aeromotive #13109, best price was on Ebay.  Best pricing I found for the fittings was from AmStreetRod.com.
 
Hope this helps,
Joe
----- Original Message -----
Sent: Tuesday, September 26, 2006 7:55 PM
Subject: [FlyRotary] Fw: Constant Pressure Differential??

I thought some of you might be interested in Aeromotive's response to my question about their fuel pressure regulators - some of which reference "Vacuum/Boost" and some descriptions only refer to "Boost".
 
Ed
 
----- Original Message -----
Sent: Tuesday, September 26, 2006 5:59 PM
Subject: RE: Constant Pressure Differential??

Ed,

 

In all cases where an Aeromotive regulator is able to be referenced to intake manifold pressure, it will affect fuel pressure on a 1:1 ratio with PSI, in both positive and negative pressure situations, equally.

 

Vacuum is normally measured in “HG (inches mercury) and you would have to convert to PSI by dividing the “HG by 2. 

 

This will ensure that the delta across the injector of flow orifice will always be maintained.

 

Hope this answers your questions, good luck and thanks for choosing Aeromotive!

 

Brett Clow

Technical Support

Aeromotive, Inc.

7805 Barton St.

Lenexa, KS  66214

913-647-7300  Ext. 109


From: Ed Anderson [mailto:eanderson@carolina.rr.com]
Sent: Friday, September 22, 2006 1:55 PM
To: tech@aeromotiveinc.com
Subject: Constant Pressure Differential??

 

I notice that some of the descriptions for your fuel pressure regulators that are manifold referenced  refers to "Vacuum/Boost" and others refer only to "Boost". 

 

 Does this indicated that those which described as "vacuum/boost"  will cause the fuel pressure to vary in order to maintain a constant pressure differential between the fuel and the manifold pressure whether below 30 inch Hg or above 30" Hg?    Does the ones which are reference to only "Boost" indicate that the regulator holds the line fuel pressure constant until the manifold pressure goes above 30" Hg and then increases it to compensate for more fuel needed in boost?

 

I am using an EFI that requires a constant pressure differential between the line fuel pressure and the manifold pressure for optimum performance.  The engine produces approx 200HP.  Therefore, I need a fuel pressure regulator which DOES vary line fuel pressure in order to maintain a constant pressure differential across the injector at manifold pressures below 30" Hg.  So do all your manifold referenced fuel pressure regulators do this OR only those which are referenced to "vacuum" or "vacuum/Boost"?

 

Thanks

 

Ed

 

Subscribe (FEED) Subscribe (DIGEST) Subscribe (INDEX) Unsubscribe Mail to Listmaster