1970 z28 correct fuel lines

Discussion in 'Original Drivetrain Topic' started by maguyvr, Apr 12, 2016.

  1. maguyvr

    maguyvr Member

    Messages:
    52
    Likes Received:
    0
    Joined:
    Feb 25, 2015
    Location:
    Woodland,ca
    I'm trying to install the correct fuel lines back onto my 1970 LT1 350. The carb has been changed from the original 780 Holley to a 750 and has 3/8" outlet fittings on it. I ordered the OEM style 3 piece lines and block fitting from Camaro Central. The line from the pump to manifold isn't even close to fitting. Maybe it's bent? And then the lines that go from the block to the carb are 5/16" and the carb inlet is 3/8". I'm assuming that they were originally 5/16". Besides getting either a straight (or correct) line from the pump to fuel block, do they make a fitting for the Holley that is for 5/16" line? Thanks for any help you can provide!
     
  2. INSPECTOR57

    INSPECTOR57 Veteran Member Lifetime Gold Member

    Messages:
    491
    Likes Received:
    25
    Joined:
    Sep 14, 2007
    Location:
    Stillwater, Oklahoma 74075
  3. Zspoiler

    Zspoiler Veteran Member

    Messages:
    3,779
    Likes Received:
    366
    Joined:
    May 6, 2012
    Location:
    Federal Way, Washington
    You are going to starve your engine if you run a 5/16 line from the fuel pump to the carb.5/16 lines are generally return lines. .I would run a 3/8 line from your fuel pump to your carb, I believe that there are prebent lines out there.If not you can always make your own.
     
  4. 70 SS/L78

    70 SS/L78 Veteran Member Lifetime Gold Member

    Messages:
    2,842
    Likes Received:
    126
    Joined:
    May 5, 2005
    Location:
    Rockford, MN
    All pre-bent fuel lines will still need tweaking & bending to make them work. I purchased 2 different line kits on my L78 and neither one of them worked without more bending.
    As far as your fuel bowl fittings you should be able to get the 5/16 bowl fittings you need to work with your reproduction fuel line kit.

    Contact Eric at Vintage Muscle car parts... sales@vintagemusclecarparts.com
    He will have the correct black zinc bowl fittings.
     
  5. giggity

    giggity Veteran Member

    Messages:
    1,339
    Likes Received:
    276
    Joined:
    Mar 18, 2013
    Location:
    Pearland, texas
    Ive recently been reading about 70 fuel lines, and apparently 70s came with 2 different sized fuel lines. 5/16 and 3/8. the routing for each should be the same , our cars did not have a return line, as far as I can tell they didnt have a coal filter, but ive read some posts that said some California cars came with them.

    I wish you lived closer Id make you a deal on my factory line, Im putting in an electric pump, and using braided line, adding a return. I really have no need for the factory line, even though im using it for a return.
     
  6. COPO

    COPO Veteran Member Lifetime Gold Member

    Messages:
    19,619
    Likes Received:
    1,704
    Joined:
    Sep 15, 1999
    Location:
    Ontario, Canada
    Stock 70 Z28 uses 3/8 from the pump to the brass block in then the 2 outs into the carb are 5/16. If someone in the past used the Holley chrome straight line with the 2 fittings then this will all be 3/8 and you will have the larger fittings in the front and rear bowls.

    Check out my website.
     
    2ndGenCrazy likes this.
  7. Matt69406

    Matt69406 Member

    Messages:
    30
    Likes Received:
    0
    Joined:
    Mar 19, 2017
    I know this is an old post, but I have ran into this issue. Are the 5/16 inlet fittings supposed to be black? Fuel line kit I purchased has 5/16 male fittings, but my 1970 Z28 carb (list 4555) has 3/8 female. I'm guessing the fittings in the carb have been changed at some point. I am going to get fittings and just wanted to make sure the 5/16 was correct and also should they be black? Any input would be appreciated!
     
  8. 70lt1z28

    70lt1z28 Veteran Member Gold Member

    Messages:
    3,953
    Likes Received:
    871
    Joined:
    Oct 3, 1999
    Location:
    Beavercreek, Ohio, USA
    5/16 is correct and they should be black.
     
  9. COPO

    COPO Veteran Member Lifetime Gold Member

    Messages:
    19,619
    Likes Received:
    1,704
    Joined:
    Sep 15, 1999
    Location:
    Ontario, Canada
    Black inlets for the 2 5/16 lines. The rest was a 3/8 line.
    82291E61-194A-403F-8E8F-5AA1E753E8A0.jpeg

    DC1CBFE0-BE7D-4361-9C1B-C82D6BB68054.jpeg
     
    Last edited: Jul 27, 2020
  10. l16pilot

    l16pilot Veteran Member Lifetime Gold Member

    Messages:
    1,933
    Likes Received:
    171
    Joined:
    Dec 13, 2004
    Location:
    Hurlock, MD, USA
    1100 original mile 70Z, Van Nuys, 03C TH400 car....but I do not see why the fuel inlet fittings would be any different than other Holley versions on the 70Z. Look closely and you can clearly see the black finish. Could this have been a running change in production?
    0.jpg
     

Share This Page