Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Buick Big Block in a K5?

Discussion in 'The Garage' started by sled_dog, Sep 8, 2003.

  1. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    I'm looking at a car with a Buick 455 in it and thinking hard on buying it and puting it in the K5. Price is right is just how much work would puting it in be? Would motor mounts bolt right up? And would it bolt to my SM465?? Could a BOP motor bolt to my 465 fine?
     
  2. RingMaster4x4

    RingMaster4x4 1/2 ton status Premium Member

    Joined:
    Mar 4, 2001
    Posts:
    2,049
    Likes Received:
    0
    Location:
    Bartlett, Texas
    No a BOP Bolt patterned big block will not fit a standerd chevy bolt pattern.
     
  3. prjt_blzr

    prjt_blzr 1/2 ton status

    Joined:
    Mar 4, 2001
    Posts:
    352
    Likes Received:
    0
    Location:
    COS, CO
    I did this swap about 15 years ago. The Buick 455 is a good truck motor. You need to fab the motor mounts. The easiest way is to bolt 1/4" plate to the Buick block and cut the center out of the chevy mount to allow them to be welded together. It takes less than an hour to do that. The stock buick manifolds will clear the K5 frame. The oil filter is a very tight fight but it can be relocated to make it easier to change. Also be careful of the motor placement to allow clearance for the driver side head and the firewall seam. I used a TH400 behind my motor. I have seen BOP scattershields that should work to bolt up the tranny of your choice. What year motor and heads are you using? The pre '72 blocks had overheating problems at RPMs and the later models had mostly smog heads. The pre and post '72 models can not be mixed due to different coolant passages. I would also recomend that you get the high volume replacement oil pump. Oh, and I wouldn't bolt this to a 1/2T rear axle. It makes a lot of low end grunt. My 455 made over 550Lb/ft of torque.
     
  4. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    yeah i am puting a 14 bolt under the truck in a couple weeks so no worries there. I know they make plates that can go between BOP motors and Chevy trans but I don't know if it would work with my SM465. I was wondering if there was a header option, I really doubt it. Was thinking shorties. Are all BOP motor mounts the same? Cause I know where I can get a set of mounts designed to bolt a Pontiac motor into a Chevy engine bay. If the Buick used the same motor mounts that could work real well. It is a 73. I was told thats 71cc chambered heads, sounded like it would still be an alright motor for me. With a nice tow cam from comp cams or something and an edelbrock intake, freshen and port match heads.
     
  5. prjt_blzr

    prjt_blzr 1/2 ton status

    Joined:
    Mar 4, 2001
    Posts:
    352
    Likes Received:
    0
    Location:
    COS, CO
    You would be better off to buy a lakewood or ?? scattershield with the BOP bolt pattern and then machine it if need be to bolt up the trans. These things are strong and you will not have to worry about grenading the clutch. I never found a set of headers for that truck but never looked that hard. The Buick motor likes low RPMs (I could light off 35s with 4.10 gears through most of second gear)and I rarely wound it over 4,500. I'm not sure headers would be real helpful with that motor. Use a good factory manifold and run 2.5" duals. I ran a mild tow cam with mine as well as the edelbrock intake with a couple of carbs. The best carb was a 750 double pumper for that motor. The new holley truck carb would be the way to go now though. I don't know about the motor mounts from the pontiac. Try calling a parts store and get numbers for both. The mounts really are easy to make though if you can not buy them. I also ran a 455 badge on my K5. It really confused people /forums/images/graemlins/smile.gif
     
  6. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    well what about the th400 option? hmm I will be running 4.10s and 38s so th400 won't work out most likely but what about bolting one to a transfer case? i have BOP 400s just sitting in stock in my garage but have no idea whats involved with converting it to 4 wheel.
     
  7. kennyw

    kennyw N9PHW Premium Member

    Joined:
    Jun 9, 2002
    Posts:
    13,224
    Likes Received:
    94
    Location:
    Stevens Pass Highway, WA
    If you already have a BOP TH400 the only thing you need to do is change out the output shaft to a 4x4 version. But that is one of the first parts to go into the tranny during a rebuild so you have to tear down the whole tranny to change it.
     
  8. prjt_blzr

    prjt_blzr 1/2 ton status

    Joined:
    Mar 4, 2001
    Posts:
    352
    Likes Received:
    0
    Location:
    COS, CO
    Just what kennyw said on the install. Based on how my 455/4.10s and 35s ran, I think that 38s would cause the motor to bog a bit on take off. I believe that there are lower gears sets for the TH400 but not sure how much lower.
    Good luck!!
    Mike
     

Share This Page