mounting a glass hood scoop on a steel hood

Mopar Body and Trim

  1. burrpenick

    burrpenick '69 Barracuda

    Messages:
    414
    Likes Received:
    25
    Joined:
    Jan 16, 2008
    Location:
    Florida
    Local Time:
    1:37 PM
    I know many say they always crack if glassed on a steel hood, but what about riveting- is there a method where the rivet head could be countersunk and covered?
     
  2. Demonracer

    Demonracer 71 Demon 00 Ram 16 Chrysler 300S 05 Caravan FABO Gold Member

    Messages:
    4,891
    Likes Received:
    2860
    Joined:
    Jan 31, 2010
    Location:
    Cleveland, Texas
    Local Time:
    1:37 PM
    Is the scoop going to be functional?
     
  3. moparmat2000

    moparmat2000 FABO Gold Member FABO Gold Member

    Messages:
    18,890
    Likes Received:
    7874
    Joined:
    May 13, 2010
    Location:
    Grand Tetons
    Local Time:
    1:37 PM
    The cracking problem probably has to do with the different rates of expansion and contraction under heat and cold cycling of steel sheetmetal vs the fiberglass scoop. What can possibly bridge that gap between those rates is using JB weld to bond and rivet the scoop in place. This should help bridge that rate of expansion, then use an autobody filler such as dyna glass over the JB weld glue joint.
     
  4. burrpenick

    burrpenick '69 Barracuda

    Messages:
    414
    Likes Received:
    25
    Joined:
    Jan 16, 2008
    Location:
    Florida
    Local Time:
    1:37 PM
    well not really..........
     
  5. burrpenick

    burrpenick '69 Barracuda

    Messages:
    414
    Likes Received:
    25
    Joined:
    Jan 16, 2008
    Location:
    Florida
    Local Time:
    1:37 PM
    Anyone have an old/maybe damaged scoop to sell?
     
  6. dodgedifferent2

    dodgedifferent2 Well-Known Member

    Messages:
    2,650
    Likes Received:
    461
    Joined:
    Aug 8, 2008
    Location:
    southwestern, Ontario
    Local Time:
    1:37 PM
    I pop riveted a six pack scoop on to my steel hood.
    I then fiberglassed things smooth.
    I fine tuned with some body fill and had it painted.
    Has been about 4 years. No cracking as of yet.

    Mine is functional. I also braced the underside hoping to take out some flex.
     
  7. Mouse action

    Mouse action Well-Known Member

    Messages:
    385
    Likes Received:
    712
    Joined:
    Oct 16, 2019
    Location:
    Brooklyn
    Local Time:
    2:37 PM
    Mine had the studs already in the scoop.
    I sealed it around with a soft door edge mouldings. DDDA31B4-AC34-4C13-8E8D-C65E99D84990.jpeg
     
    • Like Like x 2
    • Agree Agree x 1
    • A Body 440 WHY NOT

      A Body 440 WHY NOT Well-Known Member

      Messages:
      358
      Likes Received:
      140
      Joined:
      Sep 28, 2019
      Location:
      Jersey
      Local Time:
      11:37 AM
      Body panel adhesive
      Crazy strong
       
      • Like Like x 1
      • Agree Agree x 1
      • str12-340

        str12-340 FABO Gold Member FABO Gold Member

        Messages:
        1,784
        Likes Received:
        1050
        Joined:
        Dec 26, 2012
        Location:
        Vashon, WA
        Local Time:
        11:37 AM
        why not go the Ma Mopar route and put studs in the scoop and bolt that baby on - no crack problem there...
         
        • Agree Agree x 1
        • moparmat2000

          moparmat2000 FABO Gold Member FABO Gold Member

          Messages:
          18,890
          Likes Received:
          7874
          Joined:
          May 13, 2010
          Location:
          Grand Tetons
          Local Time:
          1:37 PM
          I put an aftermarket dart sport scoop on my kids 69 barracuda hood. The stud holes in this scoop were dpot on for the factory access holes in the structural web underneath. It's going to stay a bolt on setup. Not moulding it in. You can get fiberglass bolt on hoods from stinger fiberglass with a six pack scoop already moulded in.

          Screenshot_20190804-090603_Gallery.jpg

          20200427_063832.jpg
           
        • GREEN DART 5

          GREEN DART 5 Well-Known Member

          Messages:
          101
          Likes Received:
          80
          Joined:
          May 31, 2017
          Location:
          NOR-CAL
          Local Time:
          11:37 AM
          Last year I added a fiberglass scoop to a metal hood with pop rivets about every 2 1/2” then used Bondo to mould it in. The rivets aren’t perfectly lined up because I tried to hide them on the bottom side of the hood.
          Used this method back in the 80’s on a different hood and it held up great.
          However you mount it, make sure it will not flex. BCEECCD2-C09D-4584-B373-0A74059B93B6.jpeg
           
          • Like Like x 1
          • moparmat2000

            moparmat2000 FABO Gold Member FABO Gold Member

            Messages:
            18,890
            Likes Received:
            7874
            Joined:
            May 13, 2010
            Location:
            Grand Tetons
            Local Time:
            1:37 PM
            What also helps is when you rivet it on, to use backup washers under the rivet rails to reinforce the mounting. This means you need somebody to help you by holding the washers in place while you pull the rivets, but makes the attachment a bit stronger than just using the hood sheetmetal.
             
            • Agree Agree x 2
            • Like Like x 1
            • Daves69

              Daves69 Well-Known Member

              Messages:
              5,571
              Likes Received:
              3890
              Joined:
              Feb 20, 2011
              Location:
              WestOfChi
              Local Time:
              1:37 PM
              Lol, a :eek: "riveting" experience .............
              upload_2021-2-28_9-19-45.png
               
              • Like Like x 1
              • moparmat2000

                moparmat2000 FABO Gold Member FABO Gold Member

                Messages:
                18,890
                Likes Received:
                7874
                Joined:
                May 13, 2010
                Location:
                Grand Tetons
                Local Time:
                1:37 PM
                If you ever want to get perfect spacing for rivets it's a simple math equation. Total length from point A to point B in a straight line divided by the number of total spaces you want between the rivets. This will give you the rivet on center spacing in decimal form. I use it all the time doing sheetmetal patches on aircraft.
                 
                • Like Like x 1
                • Dfr360cuda

                  Dfr360cuda Diagnosis... Plum Crazy.

                  Messages:
                  1,722
                  Likes Received:
                  1095
                  Joined:
                  Aug 30, 2012
                  Location:
                  Finleyville, PA
                  Local Time:
                  2:37 PM
                  1976 to 78 I had a Camaro. I put an L88 scoop on it with fiberglass. Never had a problem. It was functional so a lotta heat was not trapped under the hood.
                   
                • leblanc

                  leblanc member 2883

                  Messages:
                  2,204
                  Likes Received:
                  358
                  Joined:
                  Jun 5, 2006
                  Location:
                  Dieppe,NewBrunswick,Can.
                  Local Time:
                  3:37 PM
                  My 76 Dart Sport Got its fiberglass scoop put in in 78-9 by a good body shop owner. He put about 3/4'' of body filler and sunk in the scoop. The first crack appeared about 4 years ago. It never moved!!!
                   
                • burrpenick

                  burrpenick '69 Barracuda

                  Messages:
                  414
                  Likes Received:
                  25
                  Joined:
                  Jan 16, 2008
                  Location:
                  Florida
                  Local Time:
                  1:37 PM
                  How easy did the scoop bend/conform to that ridge in the center of your hood. My hood is probably a 67 and has two ridges that the hood inserts laid into. Thanks, George
                   
                • Daves69

                  Daves69 Well-Known Member

                  Messages:
                  5,571
                  Likes Received:
                  3890
                  Joined:
                  Feb 20, 2011
                  Location:
                  WestOfChi
                  Local Time:
                  1:37 PM
                  Piece of cake. The '69 slope is not steep or abrupt there. PM sent.
                   
                • A Body 440 WHY NOT

                  A Body 440 WHY NOT Well-Known Member

                  Messages:
                  358
                  Likes Received:
                  140
                  Joined:
                  Sep 28, 2019
                  Location:
                  Jersey
                  Local Time:
                  11:37 AM
                • moparmat2000

                  moparmat2000 FABO Gold Member FABO Gold Member

                  Messages:
                  18,890
                  Likes Received:
                  7874
                  Joined:
                  May 13, 2010
                  Location:
                  Grand Tetons
                  Local Time:
                  1:37 PM
                  Sure, you can use 100° countersink pop rivets, and countersink em slightly below the top surface of the scoop, then skim body filler or dynaglass over them, but it will eventually crack around the rivets because the heating and cooling rates of the parts are different. The composites and glues of today are definitely better than 50 years ago, so it may last longer than this type of job used to last.
                   
                1. This site uses cookies to help personalize content, tailor your experience and to keep you logged in if you register.
                  By continuing to use this site, you are consenting to our use of cookies.