Fuel PSI too High

[MIKESAD50]

I'm running a Aeromotive Stealth 340 Pump with a Corvette Fuel Pressure Regulator/Filter Combo. At the rail I'm getting about 80psi.
Is the 340L/hr pump overwhelming the reg/filter and I need to switch to separate reg and filter?
I'm running -6 an hose to and from the filter, will changing return to larger -8 fix it?
Thanks, didn't get any help on ls1tech

[Clyde65]

The regulator should be knocking it to the 55-58psi needed. Maybe your regulator isn't working? What issues are you seeing? You can also plug in a scanner to see what your fuel pressure is according to the PCM.

[mongocanfly]

Make sure your reg is plumbed right..but it could be a bad reg..

[JohnR]

It's easy to mistake the return and feed on the filter/reg because you'd think the feed is in the center, but the feed is the outside fitting. The return is 5/16" and the feed is 3/8".

[MIKESAD50]

Its hooked up correctly, double checked. I havent tried to replace as it was a brand new ac delco branded filter. First Wix leaked. I have seen reports of the higher volume pumps, seems to be over 255 lph causing high pressure. Aeromotive of coarse says its a problem

[MIKESAD50]

No fuel pressure sensor.

[sprint_9]

Originally Posted by MIKESAD50

Its hooked up correctly, double checked. I havent tried to replace as it was a brand new ac delco branded filter. First Wix leaked. I have seen reports of the higher volume pumps, seems to be over 255 lph causing high pressure. Aeromotive of coarse says its a problem

I was doing some more reading on this, and learning. I didnt really find an alarming rate (a few here and there) issues with a 340lph pump and this filter/regulator, more so with the filter in general. It seems quite a few people have issues with one, switch to another and then it works.

[homemade87]

Holley has a corvette style filter now that is serviceable . If I have to replace mine I will go that route since I am already set up for it .

I too run a aeromotive pump and have had good service with the corvette filter . I am on my second one . First one was only at 54 psi . Second one is at 59 psi . The low pressure was a issue for my performance mods . Other than that I had no issues .

80psi is pretty high . I dont think the pump is overwhelming the regulator unless it is bad . If I was to guess you have a restriction in the tank return which will put the pressure where its at . I think the max pressure is around 90psi for that pump . I have heard of some having the same problem because there has some kind of plastic piece on the end of the return in the tank . I think it was on this site it was disused .

Heres where I was doing some research on the filters if anyone is interested .http://67-72chevytrucks.com/vboard/s...d.php?t=699891

[sprint_9]

Originally Posted by homemade87

Holley has a corvette style filter now that is serviceable . If I have to replace mine I will go that route since I am already set up for it .

I too run a aeromotive pump and have had good service with the corvette filter . I am on my second one . First one was only at 54 psi . Second one is at 59 psi . The low pressure was a issue for my performance mods . Other than that I had no issues .

80psi is pretty high . I dont think the pump is overwhelming the regulator unless it is bad . If I was to guess you have a restriction in the tank return which will put the pressure where its at . I think the max pressure is around 90psi for that pump . I have heard of some having the same problem because there has some kind of plastic piece on the end of the return in the tank . I think it was on this site it was disused .

Heres where I was doing some research on the filters if anyone is interested .http://67-72chevytrucks.com/vboard/s...d.php?t=699891

I changed my reply above after reading through your comment and the link you posted. Seems like the issue is more related to getting a filter that is either bad or slightly out of spec, or a return line plug like you mentioned.

After looking my setup over I too am running a 340 Stealth, with a vette filter/regulator. This is kind of all coming back to me as I think about it, but I can remember thinking about running an actual regulator, but went away from that as so many people have good luck with the vette regulator, and it plumbs a little cleaner.

[Hart_Rod]

Originally Posted by homemade87

Holley has a corvette style filter now that is serviceable . If I have to replace mine I will go that route since I am already set up for it .

Do you have a part number?

[homemade87]

Originally Posted by Hart_Rod

Do you have a part number?

Part # 12-876 . https://www.holley.com/products/fuel...s/parts/12-876

Has the built in filter and regulator . Both are replaceable . Plan to use one if I have trouble .

[davepl]

On my 1994 Corvette LT1 I upgraded to a large Aeromotive pump and the regulator was overwhelmed, resulting in too-high pressures with the factory regulator. I switched to an aeromotive regulator and all was fine.

So, if you're using a stock GM regulator, quite possible it just can't bleed off enough return flow to keep the pressure down.

[MIKESAD50]

Davepl, that is what I was reading, I wasnt sure if a larger -8 return line would help.

Homemade87, That seems to be a nice alternative. Anyone have experience with the Holley part?

I may try another AC Delco filter.
Below is the response from Aeromotive
Mike,

The “Corvette Filter / Regulator” is a known killer of higher flow pumps like the Stealth 340. You definitely need to install your Aeromotive filter and regulator. Honestly, get the regulator as close to the engine as you can, it’s a better hydraulic system that way and the engine will both run better and have better throttle response. Flow from the pump through the filter into the regulator on either side port, out the opposite side to the engine and out the bottom back to the tank.

Hope that helps, let us know if you need further assistance and thanks for choosing Aeromotive!

Brett Clow
Tech Director

Aeromotive, Inc.
7805 Barton St.
Lenexa, KS 66214
913-647-7300 Ext. 109

[davepl]

FWIW the Aeromotive regulator I wound up running still went in the stock location on the fuel rail, no new or additional plumbing needed, just a replacement of the regulator. And I did not need to change the return line or anything.

[MIKESAD50]

I expected nothing less from Aeromotive.
Thats why I was looking for real life experience.

My supplier will warranty part no problem so will try that first, then will consider Holley part. Last I will add the filter and regulator I have from Aeromotive. Just not a good package for my build.

[MIKESAD50]

Davepl, I dont have regulator on fuel rail.
I want the to be able to run regulator near the rear or half the distance from tank to engine.
Most OEM regulate at the rear and that's good for good power.