pressure regulator

[zr440]

I put in a holley pressure regulator with the bypass port in it. I\'ve been seeing a lot of people talking about restricting the return line. I guess I don\'t understand why this is done. I\'ve been running my truck with the return line to the tank directly connected to the regulator bypass port. My truck has been running fine except it does have some problems under heavy acceleration. Could this be because my fuel pressure isn\'t holding high enough under heavy acceleration? I\'m assuming restricting the return line would help this.



Josh

[Ryoung68]

Restricting the return port line sends enough fuel back to the in-tank pump to keep it cool but allows ample pressure behind the regulator for high fuel demand situations. http://www.s10v8.com/images/smilies/icon_hammer.gif

[s10carguy]

I\'d ask holley about that one. seems like it should be designed to maintain pressure for the carb. maybe you need more gph or a less restrictive filter? what\'s your fuel system specs and motor hp?

[zr440]

No idea on the hp. The fuel pump is the stock one for a 94 S10 Blazer TBI.

[s10carguy]

so you went from a 4.3L tbi to a 5.7L carb motor?



maybe put a pressure gauge between the regulator and the carb and see what you\'ve got. maybe the fuel filter is dirty and you\'re losing volume there.



if the fuel pump uses a sock in the tank they are restrictive as well. pressure doesn\'t mean much if there\'s no volume.

[zr440]

I have a gauge already. Have the regulator set to 6 psi. Although sometimes after I drive it and check it when I get home the pressure is only around 4.5 to 5 psi. No sock on the pump. I know this because I had to replace the pump once before when I still had the 4.3 in it. New fuel filter. I\'m assuming it is an issue with the jetting. I\'m running a 750 edelbrock. It just got me wondering when I see this talk about restricting the return line. From the research I\'ve done I don\'t think I need the restriction for the regulator I have - Holley 12-803BP.

[MOREPOWER]

What is the pressure under heavy accleration? IF it is 4psi i be looking at other problems.. The set up u have is same as mine.. But i have digital fuel pressure guage on mine so i know what mine is all the time.

[zr440]

I\'m not sure what it is when acceleration..my gauge is under the hood. I just wired my fuel pump to a switch so I could be sure that it is on all the time. I\'ll see how that goes.

[Diezel]

this sounds like the same trouble im having with mine. Let me know how it goes.