Those with Accufab regulators, does your FP change?

[blackbuick87]

My regulator likes to gradually lower itself. I always run 45psi (Thrashers) and a while ago I started getting a little knock. I check the fp and its at 38psi
Reset it to 45psi, after about a month I checked it today and its at 40psi. The only reason I looked today is because I lost 3psi of boost, and found a split hose on the vacuum block.

So anyways I try to tighten it as much as possible without stripping something or bending the allen wrench. Anyone else notice this?

 

[REDS HOT AIR]

you checking it with line on or off?

no need to strip it out the bolt aint gonna turn

 

[DR BOOST]

on the allen screw is a check nut. if you dont tighten the checknut,it will loosen by itself and lower the fp. dont ask how i know


surej

 

[blackbuick87]

Yes I tightened the nut and check the fp with the line off. I am dense, but not that dense

 

[S10xGN]

Mine stays set pretty well, but it doesn't track like it should:

Accufab FP pressure regulator "RISE" rate:

boost------------pressure-----------------fuel pressure "rise"

----0--------------44--------------------------0
----5--------------46--------------------------2
---10--------------51--------------------------7
---15--------------55-------------------------11
---20--------------61-------------------------15

Don't know that it hurts anything (at least not according to the EGT° and O2's)...

 

[REDS HOT AIR]

I have a kenne belle on mine which is a accufab and its never gave a problem

1# per # of boost and always right where I set it

 

[FreddieWilliams]

Bob,

I geuss if the spring inside the regulator lost some of its tension over time, it would result in a lower static fuel pressure. Although I have not heard of this happening before your post.

Purhaps your drop in static fuel pressure is due to a failing fuel pump or increased voltage drop to pumps supply voltage.
You might want to verify you have very little voltage drop back at your fuel pump (i.e hot wire fuel pump).


S10xGN,

Purhaps your difference in increased fuel pressure vs boost is due to a error in your boost gauge reading and not a problem with the regulator at all.
It appear to be reading 3 psi higher at lower boost level and ~4-5psi at higher boost levels.

Just a thought.

 

[Mustang 1]

I have been through this before.I had the same regulator and a hot-wired 307.It seemed daily that I diaed up the fuel pressure.I replaced the regulator with a different billet unit and I also replced the pump with a 340.I thought the problem was fixed for a day. The next day the pressure dropped I again upped the fuel pressure. I ordered a new gauge and it was the gauge that was giving me the readings wrong. Upon replacing the gauge I actually had 60 psi at idle..No wonder I was running rich!So now I have some extra parts for my fuel system-_ would check the gauge first.Just a thought!