I’ll check it again Ed, but mine varies. I thought the whole idea of being MAP referenced is to react to the MAP changes? Other ways we it can keep the pressure constant without the MAP reff.
Buly


On 1/22/05 7:42 AM, "Ed Anderson" <eanderson@carolina.rr.com> wrote:

Hi Buly,

Actually, I have a manifold referenced pressure regulator (which if I understand the concept) attempts to keep the pressure differential between the fuel side and manifold side of the injector constant. However, Varying engine manifold pressure (varying throttle opening) does not appear to have any affect on my fuel pressure.  It sits rock steady at 40 psi with one pump and goes up to 43 psi with both running regardless of throttle position.  I would expect that as manifold pressure rises from opening the throttle that the fuel pressure would rise to keep the pressure differential constant - but, if that is indeed happening, I can not detect it.

Ed A

 

----- Original Message -----
 
From:  Bulent  Aliev <mailto:atlasyts@bellsouth.net>  
 
To: Rotary motors in aircraft <mailto:flyrotary@lancaironline.net>  
 
Sent: Friday, January 21, 2005 7:57  PM
 
Subject: [FlyRotary] Re: Fuel Injector  Sizing
 

On 1/21/05  6:37 PM, "Ed Anderson" <eanderson@carolina.rr.com>  wrote:

 

George, my fuel  pressure gauge reads between 40 and 43 psi depending on whether I have one  or both pumps on.  I fly with 40 psi (one pump).   My pump  (with no flow) will give a pressure of 80 psi, but a regulator keeps it at  40-43 psi.  I generally check my pumps for their no-flow pressure and  have noticed over the 6 years that the pressure of the main pump has  decreased from 80 psi to 60 psi - so getting near replacement time.   The spare pump still produces 80 psi - less wear as it is normally  only on for take off and landing.

Ed  A

Hi Ed, do you set your fuel pressure without the engine  running or with? The MAP varies the FP while running, so I Assume 37 psi  without engine  running would be the benchmark?
Buly