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New Injectors!

Discussion in 'Performance & Fuel' started by reggiecab2000, Sep 24, 2012.

  1. reggiecab2000

    reggiecab2000 Rockstar 4 Years 500 Posts

    PART 1:

    Alright guys I replaced my poppet fuel injectors with the new updated MFI injectors (SCPI to MFI) on my truck. Started about noon and finished around 5.
    here some of the process...

    after removing the air intake...

    photo 1 (2).jpg
    most all of the connections out of the way

    photo 2 (2).jpg
    upper intake off, i had to remove the thermostat because it blocked the upper intake from coming out :/
    look at all the black crap built up in there.
    photo 3 (2).jpg

    dirty old nasty injectors..

    photo 5 (2).jpg

    heres a quick comparison

    photo 4 (2).jpg

    this photo was after my careful cleaning, didnt wanna clean too much and worry about getting the cleaner i used into the port holes and messing something up, so i used it wisely...

    photo 4.jpg

    The new injectors in place

    photo 5.jpg

    End result???
    I can definitely feel a smoother idle, it seems to run very smooth now. Seems like a might have picked up a little peppiness in my engine too, although i wasnt expecting too...
    however this did NOT fix my cold start misfires :/

    i think i may have found the culprit...

    PART 2:

    does anyone think that THIS crack can cause possible condensation in the cap or anything to cause misfires???

    photo 1.jpg

    also look at this, no bolt in there holding the fuel lines to the block, which actually saved me some time.
    photo 3.jpg

    Looks like the shop who replaced my lower intake gasket only about 2 months ago overtightened my cap and cracked it and my distributor, AND they forgot to put a bolt back into place for my fuel lines!
    I will be going back to them later this week to show them the pictures and see if they believe what i am saying. Im pretty set now that they are the reason my truck started misfiring again, gahhh this is why i do all my own work!
    I make sure i have everything put back in right!

    other than that rant, I can definitely feel a smoother truck and it also seems to start up quicker too, which it already started pretty quick anyway, hopefully ill see something in the MPG dept as well
  2. Conlan Rose

    Conlan Rose Active Member 2 Years 1000 Posts

    So what the actual difference between CSFI and MFI?
  3. reggiecab2000

    reggiecab2000 Rockstar 4 Years 500 Posts

    the only difference i know of is from a reliability standpoint, the poppet valves are notorious for clogging up and the MFI upgrade supposedly is not as susceptible to that
  4. Conlan Rose

    Conlan Rose Active Member 2 Years 1000 Posts

    Makes sense but which is more efficient and more technologically advanced. All new Chevy trucks use SFIso which is the better.
  5. reggiecab2000

    reggiecab2000 Rockstar 4 Years 500 Posts

    the updated MFI injectors are more efficient and more technologically advanced, i dont know about the difference between them and the SFI your speaking of, but definitely more so than the poppet valves

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