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will a 402 Big block mount up to my 4 speed?

Discussion in '1969-1972 K5 Blazer | Truck | Suburban' started by Rix_Gotta_Blazer, Mar 11, 2003.

  1. Rix_Gotta_Blazer

    Rix_Gotta_Blazer 1/2 ton status

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    i recently purchased a 402 big block out of a 71 Monte Carlo. i alrady have a 350 witha 4 speed, granny low and a np205. my question is how easily will the 402 mount up to the 4 speed? should it line right up? will the bell housing line up properly with the tranny? your replies are appreciated, Rick /forums/images/graemlins/truck.gif 70 stepside
     
  2. ZonkRat

    ZonkRat 1/2 ton status

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    Every thing should swap right over.I did the same swap on a 72 K5 and didnt have to change anything except exaust and lenghten a couple of wires.The only prob might be the oil pan on some motors.I didn't have to change mine,but,some are a little diff.402 is internal balance so the flywheel is OK.I would go to 12in clutch if possible,the BB does have more torque.
     
  3. Rix_Gotta_Blazer

    Rix_Gotta_Blazer 1/2 ton status

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    the reason i am changing out the motor is the "easy access" factor. the clutch went out when i took it to the truck pulls, so i am in the process of puttin in a new clutch. i just bought a stage 2 centerforce clutch and i am waiting on the motor swap. the clutch is a 12 inch 10 spline. im worried most about the clutch linkage. as it is now, the linkage squeezes right through two of the header tubes.
     
  4. Don

    Don 1/2 ton status

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    Yep! It's a direct bolt in. You'll need mount's, hose's, that kinda crap but it will shoehorn right in there! /forums/images/graemlins/shocked.gif /forums/images/graemlins/grin.gif
     
  5. R72K5

    R72K5 Banned

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    12" clutch is what factory put with the BBc engines and most 4 bbl 350's too.

    as long as you find correct exhaust, motor mounts brackets, and etc then youll have it in in no time, oil pans not an issue, all are rear sump /forums/images/graemlins/laugh.gif
     
  6. Don

    Don 1/2 ton status

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    Dumped a 454 in My 71 last June. What a difference, replacing an old, tired, Sick 350, with a fresh 454! YEEHAAA! And the 454 actually get's better Mileage than the whooped out 350! /forums/images/graemlins/eek.gif
     
  7. OLD DAWG

    OLD DAWG 1/2 ton status

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    Sorry about nabbing your post /forums/images/graemlins/crazy.gif. But hey Don, I've got a very tired original (not rebuilt) 350 and I also have a lonley 454 just waiting for a nice home. What type of mounts and such did you (or others) use?
    Thanks;Doug:aka: /forums/images/graemlins/k5.gif OLD DAWG
     
  8. rchandler

    rchandler Registered Member

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    smallblock mounts will work. and yes some oilpans will be too big. you will have to use one out of one of these trucks or a car. everything else will bolt up nicely /forums/images/graemlins/thumb.gif
     
  9. Don

    Don 1/2 ton status

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    Just used new Motor Mount's from N.A.P.A. they worked good, had to trim a little off to get header's to fit, but other than that, just stock replacement part's. /forums/images/graemlins/smile.gif
     
  10. '72brett

    '72brett 1/2 ton status

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    [ QUOTE ]
    had to trim a little off to get header's to fit,

    [/ QUOTE ]

    I don't get it... you had to trim off part of the motor mounts to get the headers to fit?
     
  11. OLD DAWG

    OLD DAWG 1/2 ton status

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    Thanks for the info guys. The sound of a healthy Big-Block is a gear heads answer to viagra /forums/images/graemlins/thumb.gif
     
  12. Don

    Don 1/2 ton status

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    [ QUOTE ]
    [ QUOTE ]
    had to trim a little off to get header's to fit,

    [/ QUOTE ]

    Yes I am using Hedman Hedder's, and they would have rubbed on the upper right hand corner, if i did'nt releive the motor mount a little on the driver's side.
     

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