In tank fuel pump [EP381] with carburetor - temporary setup

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dustin rhodes

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Hi everyone first time poster :) , I’m looking to LS Swap down the road but for now would like to temporarily use the new tank with the EP381 in tank Fuel pump. How would I go about setting it up to use with the carburetor that it has now which is a quadrajet on a BBC 402. I was thinking that a simple fuel pressure regulator would be enough am I correct or would I need something else? Any advice or input would be greatly appreciated.
 

Ricko1966

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A good bypass regulator, if that's what you meant by a simple regulator than yes. If you meant a cheap deadhead regulator than, no.
 

dustin rhodes

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Hi Ricko1966 thank you for the info. I have a new Holley FPR in my tool box that I was thinking about trying it’s model Holley 12-804 what would be your opinion on this specific type of fuel pressure regulator.
 

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ali_c20

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You need a fuel pressure regulator with return and it has to be matched to the pressure output of your fuel pump. The Holley 12-804 has a maximum inlet pressure of 7 psi.
The in tank fuel pump puts out ~ 60 psi .
This could work for your application:
https://www.summitracing.com/parts/fsy-fpr-1001
 

dustin rhodes

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@ali_c20 thank you for your help. I will order it this coming payday and will report back as soon as it arrives. I appreciate everyone’s input and help thank y’all for sharing your knowledge.
 

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Hi Ricko1966 thank you for the info. I have a new Holley FPR in my tool box that I was thinking about trying it’s model Holley 12-804 what would be your opinion on this specific type of fuel pressure regulator.
I didnt bother answering because by the time I saw this Ali had given you proper advice. The regulator you have is a deadhead regulator. It just prevents flow through to regulate pressure on the outlet side, but restricting flow also restricts volume and can put serious dead head pressure on the pump. Not good for pumps. A bypass regulator allows full volume but allows excess fuel to pass through the regulator reducing pressure at the carb. Also since fuel is constantly moving instead of just coming to a point and stopping or slowing drastically, the fuel and pump stay cooler.
 
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dustin rhodes

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Hi guys yesterday was payday so I ordered the correct regulator. I will update how the installation goes. Again I appreciate every one of you that took the time to chime in and help me out.
 

Ricko1966

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Hi guys yesterday was payday so I ordered the correct regulator. I will update how the installation goes. Again I appreciate every one of you that took the time to chime in and help me out.
By sure to use fuel injection hose and clamps
 

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dustin rhodes

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@Ricko1966 the original 402 that is in it at the moment has low compression on 3 of the cylinders and I was told that the heads need a valve job and the price quotes that I have gotten for having it rebuilt are insane. I figured that in the long run it would be best to just do an LS swap. By the way I also ordered the correct clamps and EFI hose you told me to order. Thank you again!
 

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Look at this page, check hp and torque and engine family. I wasn't going to tell you, but Im going to anyway. The reason the ls has an edge on an sbc is the heads. But any big block head already flows better than any sbc factory head. Your 402 has serious potential especially if you are comparing torque.
 

dustin rhodes

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Hey @Ricko1966 thank you for sharing that. My main reason for going with an LS swap is because my neighbor down the street has an LS with transmission that he’s willing to let go for 400$ so I’m thinking that it will be cheaper than rebuilding the 402 and I’m also taking gas mileage into consideration since it’s like $6.00

As for an update on the install .. the regulator arrived today and I have got it all installed and done tonight but I can’t start the truck because my neighbor just had a baby and it’s kinda late to be causing ruckus turning the truck on. I will try it out tomorrow and let everyone know how it goes. Again I can’t thank everyone enough for helping me out.
 

dustin rhodes

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Sorry for the late update. What a wild scene it was when I cranked the truck and gas literally poured out of the regulator and after fiddling with it for just a bit I realized it was defective. Sent it back and received another one which worked perfectly! Thanks fellas for sharing your knowledge and helping me out.
 

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Sorry for the late update. What a wild scene it was when I cranked the truck and gas literally poured out of the regulator and after fiddling with it for just a bit I realized it was defective. Sent it back and received another one which worked perfectly! Thanks fellas for sharing your knowledge and helping me out.
Part quality really sucks these days.
 
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