4.3L to 7.4L swap 92 c1500

Discussion in 'Engine & Performance' started by bosox1624, Dec 13, 2016.

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  1. bosox1624

    bosox1624 New Member

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    Hey guys,
    new to the forum and looking for some help. I am swapping a 4.3 v6 for a 7.4 v8 I am looking to get some information about the motor mounts needed. I was told that any V8 motor mount would work for this swap Does anyone know if this true? Also I am assuming the V8 mounts are taller but will the transmission mounts need to be changed as well or should the trans bolt up fine with just changing the motor mounts? Any help would be appreciated, thanks
     
  2. Mikebte

    Mikebte GMFS Member

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    The 4.3 mounts on the frame will need swapped out for V8 mounts. Easy
    What transmission do you have?
    If it's an auto transmission, you should be fine.
    Auto transmission will bolt up to a big block, being it's a 4L60 or 700r4.

    You keeping the TBI or going carb?
    Are you going to switch to a 14 bolt rear?
    What Radiator are you running?
    E fan or belt driven?
    Only ask cause I am in the same spot kind of, ether 454 or 5.3 in my 93 GMC 2500, not sure what to swap, but I have looked a lot at the 7.4 swap
     
  3. Mikebte

    Mikebte GMFS Member

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  4. bosox1624

    bosox1624 New Member

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    Sounds good. thanks for the info.
    It is an auto trans 700r4 which I will be putting TCI kit into so it will hold up.
    I am switch over to carb because I don't want to mess with all of the electronics and wiring that goes along with TBI.
    I am going to try the stock radiator and if it doesn't cool quick enough I will get one from a C2500 which should bolt up just fine except for the fan shroud
    I would like to go with an e-fan because then I won't have to worry about a fan shroud but we will see.
    The rear end I am undecided at this point
     
  5. Mikebte

    Mikebte GMFS Member

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    Well a 10 bolt will hold up, unless you plane on spinning a lot of tire, same with the trans.
    Carb is way easy, I do agree.

    And a lot of the 350 half tons have the larger radiator.
    My 2500 had the small radiator and I had to upgrade it
     

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