Results 1 to 8 of 8

Thread: Short vs long injectors

  1. #1
    Join Date
    Jan 2008
    Location
    Sweden
    Posts
    18

    Default Short vs long injectors

    Hi,
    I have got my hands on a set of rebuilt injectors for my old 6.2. My old ones are the long model but the "new" ones are short.
    As far as i can see will the short ones fit my cylinder heads but I'd better get another set of lines from the IP to the injectors.
    Have I missed something or will this work for me?
    /Nils

  2. #2
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,573

    Arrow

    What year is your "old" 6.2? The short injectors will do fine to replace long injectors with the correct lines, but if your heads are too old, the injector threads won't be the same.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  3. #3
    Join Date
    Jan 2008
    Location
    Sweden
    Posts
    18

    Default

    Threads are the same. I Think that the motor is a -87 or -88 but isn't sure. My motorhome had a 454 gasser from production but a previous owner swapped it for the 6.2 na.

    6.7 metric tonnes to drag along, I have a dragster

  4. #4
    Join Date
    Feb 2000
    Location
    Montana
    Posts
    11,382

    Arrow

    GM used short injectors in vans because of the tighter clearances inside the engine cover. I' haven't seen a direct comparison of the steel fuel injector lines used for long/short injectors. I wonder what the difference is.... Jim

  5. #5
    Join Date
    Jan 2008
    Location
    Sweden
    Posts
    18

    Default

    The difference is 0.4 inches (10 millimeters) so it is not a big difference. I'll try to bend the lines carefully. I'm afraid they are a Little brittle after 30 years.

    Thanks for the response!!!

  6. #6
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,573

    Arrow

    The lines aren't much different, but they are, and using the long injector lines on short injectors will stress them, one way or another. You're right about being brittle. That's a lot of work hardening, pounded with ~1800 PSI pulses several times a second for near 30 years. Annealing may help, but I don't know what hardness standard they require to withstand more punishment. They are steal, and stout, so it's likely no big deal. If you do bend them into submission, I recommend large radii, as gentle as possible. The fittings should align onto the injectors and pump with no stress, and secured the same. Stressed lines, even much less old, will crack.
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  7. #7
    Join Date
    Feb 2000
    Location
    Montana
    Posts
    11,382

    Arrow

    I've heard that these fuel injector lines were mandrel bent, like the free-flowing exhaust systems we all like to use on our trucks. As such, an internal slug is drawn through the steel lines as the bends are formed. This helps to maintain a kink-free bend that doesn't restrict flow.

    Now... as the inside mandrel is drawn through the tubing, it semi-cold-forges the inside of the tubing, creating a layer that is a little different from the steel found in the outer layers of the tubing. This inner-most "forged" layer is what is reported to be somewhat "brittle" when bent, causing tiny pieces of steel to flake off, which would be catastrophic to injector condition. This is worst case of course, and I imagine most lines don't do this... cuz I've bent them a little before without any apparent problem. Jim

  8. #8
    Join Date
    Jan 2008
    Location
    Sweden
    Posts
    18

    Default

    Thanks for all the info! I will skip the idea of trying to bend the lines. I dont't like the idea of trouble down the road somewhere on any trip due to a broken line. I will look for lines from a Van, they should fit.
    /Nils

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •