Getting around to firing up my car n ran into an issue. We can't get the fuel pressure down below 90 psi. I'm running a dual pump hanger with two 255 walbros. 8an feed 6an return a1000-6 reg, atleast it's supposed to b n that's what it looks like but there is no marking on it other than 0610(got it used). There is no kinks/obstructions in the return line and it is making it into the tank fine. Tore the reg apart n it looks fine. The spring seemed really stiff so after trying everything else we decided to cut it down a lil bit which got it down to 100(started at 120+), trimmed it down a lil more till where there is no preload on the spring n were at 90~. I can back the bolt out all the way n that's as low as it will go. The only thing we can think if is that the hole where the bearing thing seats is so small(about 1/8") it can't bypass enough pressure. My tuner is gonna look at one he has at the shop tomorrow n if it has a larger hole we will try that one. Anybody ever experienced this? Or any ideas would b helpful. Thanks. Mike

 

No ideas guys? Talked to aeromotive today n they don't think it's the reg but said I couldn't use the spring with no preload so I ordered a new one

 

Could be just a bad pressure gauge. Have you tried checking fuel pressure from another location?

 

1/8" is too small. The smaller Civic regulators with 1/4" OD outlets aren't enough for a single walbro 255HP, and the hole is around 1/8" ID.

Try disabling one of the pumps. If it stays high, then the regulator just isn't working. If pressure drops, then it's probably too much flow for the regulator.

 

It could be a small orifice.. IIRC the earlier aeromotive regulators had a smaller orifice.

I'll take mine apart and measure.

but it could simply be your setup.. running a lot of pump with a low injector pulsewidth can cause base pressure to rise since the regulator can't bypass enough fuel. do as suggested and kill one of the pumps and see what the base pressure does.

 

I figured it out. It's something will the regulator. I tried an aeromotive pro efi n it worked fine. Could get pressure down to 40 or even less if I wanted. I don't think there's anything wrong with this regulator, it just won't work for my setup. Looks like I'm in the market for a new reg. :/
For future reference



This hole is too small to bypass enough fuel! Wonder if it would b worth it to try another a1000-6?!

 

that's what mine looks like as well, took it apart earlier.

my spring is pretty beastly, it's basically a valvespring... what was yours?

 

Prolly same as urs. Real stiff, just like a valve spring. I actually thought that mayb the spring was changed for the last guy to get more pressure out of it so I cut it down. I got a new spring on the way for this one but I just ordered another reg today. Fuelab 525 hopefully that will work. Thinkin bout putting this one up for sale since it don't seem bad, I just don't wanna rip someone off.

 

I might need another one lol

 

Must be somrthing wrong with the regulator. I have an a1000 -6 witha magna fuel pump and don't have any issue's lowering my pressure.

 

. What does ur magnafuel pump flow?

 

About 160gph@40psi at 14 volts. It is rated to 2000hp n/a on gas.

 

I'm also running a -8 feed line, not sure what size your using but a smaller feed may cause issue's.

 

I'm running 8an.

 

line size doesn't really matter...

regardless of how big your lines are, how big your pump(s) is/are you are flow limited by the size of the orifice in the regulator

 

Well got the spring today as well as the new reg. tried putting on the new reg but realized I would either need a female-male 90 or 45 since the return is on the side instead of the bottom(return line would hit shock tower), so I couldn't do anything with that till I would get the fitting. So I decided what the hell n tried the old one with the new spring n it worked! Couldn't really tell much diff in the springs, must've just been a hair stiffer n I noticed it was wound the opposite way. But either way it worked! Set pressure down to 50 n she fired right up!