Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: Return Line

  1. #1

    Default Return Line

    How much pressure in the return line? Not much I wouldn't think. Can the stock original 5/16" steel tube return line be used as the return for the Sniper Kit?

  2. #2
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    18,657

    Default

    There's only a few psi at the most. I prefer the same size return line as the feed (3/8"), but you can try your 5/16".
    May God's grace bless you in the Lord Jesus Christ.

    '78 BRONCO: 508" stroker, TFS heads, 11:1 comp ratio, Dominator MPFI & DIS, cold air induction, Spal dual 12" fans/aluminum radiator, dual 3" exhaust/Magnaflow mufflers, Moroso vacuum pump, Accusump, engine oil & trans fluid coolers, 100HP progressive dry direct-port NOS, A/C, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, 3:1 Atlas II, modified Dana 44/60-lockers-4.10s, hydroboost/4-disc brakes, ram-assist/heim joint steering, Cage long radius arms, traction bars, 4" Skyjacker lift, 35" mud tires

  3. #3
    Join Date
    Oct 2016
    Location
    Albuquerque, NM
    Posts
    71

    Default

    The Reference Manual (page 5) says your return should not be more than 3 psi. The Sniper Quickstart Manual (page 4, step 6) recommends at least a 5/16" line for the return. I used my factory 5/16" hard line for the return line with no issues.

  4. #4

    Default

    Cool, thanks guys. That's what I was hoping.

  5. #5

    Default

    I know the return line is only supposed to carry about 3 psi, so I was thinking I could use regular fuel hose to make the connections between my existing steel lines? Higher pressure rating is the only thing that makes the EFI hose different from standard fuel hose, right? My existing return is 5/16" and they only included 3/8" hose in the kit. I could probably use it, but I'd rather have a snug fit before I clamp it.

  6. #6
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    18,657

    Default

    Quote Originally Posted by Firebob View Post
    ...so I was thinking I could use regular fuel hose to make the connections between my existing steel lines? Higher pressure rating is the only thing that makes the EFI hose different from standard fuel hose, right?
    No, fuel injection hose for external routing has an SAE 30R9 rating for continuous & pressurized fuel flow use. This is not the same SAE 30R7 rubber fuel hose as used on carbureted applications.
    https://forums.holley.com/showthread...nts-amp-Clamps (Proper EFI Hose, Sealants & Clamps)

    My existing return is 5/16" and they only included 3/8" hose in the kit. I could probably use it, but I'd rather have a snug fit before I clamp it.
    Don't use 3/8" hose on a 5/16" fuel line, that's wrong.
    May God's grace bless you in the Lord Jesus Christ.

    '78 BRONCO: 508" stroker, TFS heads, 11:1 comp ratio, Dominator MPFI & DIS, cold air induction, Spal dual 12" fans/aluminum radiator, dual 3" exhaust/Magnaflow mufflers, Moroso vacuum pump, Accusump, engine oil & trans fluid coolers, 100HP progressive dry direct-port NOS, A/C, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, 3:1 Atlas II, modified Dana 44/60-lockers-4.10s, hydroboost/4-disc brakes, ram-assist/heim joint steering, Cage long radius arms, traction bars, 4" Skyjacker lift, 35" mud tires

  7. #7

    Default

    Danny, I realize it's not the same fuel hose, but if the only difference is its ability to withstand higher pressures. The return line doesn't carry that kind of pressure, so presumably standard hose could be used on the return only.

  8. #8
    Join Date
    Dec 2009
    Location
    Connecticut
    Posts
    18,657

    Default

    Quote Originally Posted by Firebob View Post
    Danny, I realize it's not the same fuel hose, but if the only difference is its ability to withstand higher pressures.
    That's not the only difference! As I stated in post #6 and in that LINK, it's also for continuously flowing fuel (high pressure or not).

    Quote Originally Posted by Firebob View Post
    I know the return line is only supposed to carry about 3 psi, so I was thinking I could use regular fuel hose to make the connections between my existing steel lines?
    Doesn't seem like you very much of it, so buy the proper hose.

    Quote Originally Posted by Gates Tech Tips - Permeation-Resistance Fuel Line Hose
    There are two basic types of rubber fuel hose used for automotive fuel line replacement:
    1. Fuel and oil hoses that meet the SAE 30R7 standard.
    2. Fuel injection hose that meet the requirements of SAE 30R9.

    Not Recommended: Standard Fuel and Oil (SAE 30R7) Hose
    Standard fuel and oil (SAE 30R7) hose is rated for low-pressure applications at 50 psi
    working pressure up to 3/8” size, and 35 psi for sizes over 3/8”. This general-purpose
    hose contains a light reinforcement, and the rubber materials can be any compound that
    is suitable for fuel, oil and vapors. However, Gates engineers warn that this hose is not
    suitable for use on any fuel injection system—even as a return line
    . It is not designed to
    handle the pressures or “sour gas” that can form in the return line.
    In addition, this hose
    can emit 30 times more hydro carbons than SAE 30R9 hose, making it a significant
    source of pollution.

    Recommended: Fuel Injection (SAE 30R9)/MPI Hose
    Fuel injection (SAE 30R9) or MPI (multi-port injection) hose is reinforced to handle
    higher pressures up to 180 psi. It can be used on all injection systems that use hose
    clamps, but it should not be used to replace coupled assemblies on fuel injection
    systems.
    http://www.gates.com/oreilly/tech_ti...elLineHose.pdf (Link to entire article.)
    May God's grace bless you in the Lord Jesus Christ.

    '78 BRONCO: 508" stroker, TFS heads, 11:1 comp ratio, Dominator MPFI & DIS, cold air induction, Spal dual 12" fans/aluminum radiator, dual 3" exhaust/Magnaflow mufflers, Moroso vacuum pump, Accusump, engine oil & trans fluid coolers, 100HP progressive dry direct-port NOS, A/C, LenTech Strip Terminator wide-ratio AOD/2500 RPM converter, 3:1 Atlas II, modified Dana 44/60-lockers-4.10s, hydroboost/4-disc brakes, ram-assist/heim joint steering, Cage long radius arms, traction bars, 4" Skyjacker lift, 35" mud tires

  9. #9

    Default

    Got it. I'll get what I need in the proper size.

  10. #10

    Default

    Here's a case where someone used some original hose in a Sniper installation: Disaster. No joke.

    He should have pressurized the fuel system and checked for leaks before attempting to start the engine. Instead, he was adjusting the timing while fuel sprayed under the car. He is lucky to still have a car, a garage and a life. Checking the fuel pressure and integrity of the fuel system before the first start is very important. But in that tread, it never occurs to anyone, and instead they discuss fire extinguishers.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us