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Technical Help, anybody put a sbc into a 55' Pontiac?

Discussion in 'The Hokey Ass Message Board' started by Bored Over, Apr 1, 2014.

  1. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    Looking to put a 350 Chevy into my Pontiac. Has anybody used a "hurst" style front mount? I have the engine in front of the car, and I am wearing out my tape measure. I'm also open to side mounts,but not much room. Just curious If anybody else has done this? I don't have a transmission yet, or I would have it blocked up betwen the frame rails. What have you done/ Pictures would also be helpful. Thanks..
     
  2. Why not get a core Trans case and bolt it up to the block? Then drop it in and have at it.
    That's going to save you alot if grief in the long run.

    I wouldn't hesitate to take on the project, but I wouldn't start without the Trans.
     
    Last edited: Apr 1, 2014
  3. Rusty O'Toole
    Joined: Sep 17, 2006
    Posts: 9,660

    Rusty O'Toole
    Member

    They came stock in Canadian Pontiacs. They also used the Chev chassis. I know this is not much help, just being a wisenheimer.

    Have you thought of adapting Chev mounts?
     
  4. Hotrodbuilderny
    Joined: Mar 20, 2009
    Posts: 1,646

    Hotrodbuilderny
    Member

    I won't be much help because mine has a 350, but it also has a Camaro clip.
     

  5. 1971BB427
    Joined: Mar 6, 2010
    Posts: 8,766

    1971BB427
    Member
    from Oregon

    I can't imagine it wont be a very easy swap. There's plenty of room without modifying the firewall, and after helping a friend swap in side mounts on his '56 Chevy, I bet you could use the same side mount kit the Tri 5 Chevys use too. They don't have much room for side mounts straight out from the engine, so they mount slightly forward and angle back to the side position.
    [​IMG]
     
  6. Hell!! That's gonna take all the fun right out it. :)
     
  7. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    Working on getting a trans at the moment, I wouldn't think about even starting without that and getting it mocked up. I know that there are no "kits" available, just wanting to here if anyone else has done this before and what they did. I looked at doing a nova/camaro/jag clip. Changed my mind, going basic manual steer, manual brake.
     
  8. destructo
    Joined: Mar 6, 2001
    Posts: 97

    destructo
    Member

  9. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    I've seen those mounts, and the stock style ones for the front crossmember. I could weld something like that up without a problem. I have pics on my phone, just don't know how to post them. If someone p.m.d me with there phone # I'd send them and they could post them for me?
     
  10. bryan6902
    Joined: May 5, 2008
    Posts: 1,137

    bryan6902
    Member

    I will wager that any kit for a Chevy will not work, without modification, in your Pontiac. Why don't you fab side mounts and put a later model Pontiac engine/transmission in it?
     
  11. Biggest problem with any engine swap in these cars is steering clearance for the left manifold and downpipe. The master is also under the floor not leaving a lot of room once you do get past the steering. This is because the 55-57 cars use essentially the same chassis as 49-54 Pontiac cars, which were engineered for inline engines. Pontiac's solution was to dump the left manifold out the front and cross over in front of the motor.

    Some guys mount the motor offset to the right an inch or two, you can track down various stock manifolds that may work, or frankly what I would do is clip the damn thing and not have to worry about the kingpin front end or finding scarce/expensive parts to rebuild it. At least one Pontiac guy I know of says you don't want to run radials on it either, because of the kingpins, although how that will hurt I've no idea.

    The Pontiac frame is completely different from a Chevy, it's more like an Olds if anything; one problem with the change is the side mounts on later motors need some gymnastics done because if you just come straight out to the frame you go right into the upper A-arm mount. A few years ago a buddy had a '56 Olds someone cobbed a 350 into and it didn't even have a mount on the left side, or if it did it had broken off from poor welding; the one on the right was just a piece of 1/2" bar stock with a tube welded to the end to take the motor mount bolt.



    I have a '57 more-door I'd love to do something with, but I think before anything I'd clip it and normally I'm anti-clip. I'm even wondering if I can trim enough of the front suspension and frame away to stick a Jaguar XJ front end in it and not have to cut the entire frame stub off.

    I would also suggest changing the master cylinder to a firewall mount just for ease of working on it and upgrading it. There's no kit for the stock one and unlike a 49-54 Chevy under floor deal there's no easy way to alter it to hang a later style behind it.


    FWIW, if you end up with a Trans Am or the Jag front end, a Trans-Am/Camaro rear should be a direct bolt-in to give you matching wheel bolt patterns all around.


    And as some have noted, the Chevy isn't a great choice unless you're on a budget, a Pontiac V8 will go in for the same amount of work and be just as reliable.
     
  12. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    I have thought about the camaro/nova/jag front end swaps. Problems are that I would have to find them, rebuild them, weld them in. lus I still have to do motor/trans mounts. What is so bad about the king pin suspension if it is in good shape? I plan a bigger front sway bar and firewall mounted master anyway,since the defroster box is gone.
     
  13. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    I would love to use a pontiac engine, I just don't have one!
     
  14. randy
    Joined: Nov 15, 2003
    Posts: 679

    randy
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  15. 1971BB427
    Joined: Mar 6, 2010
    Posts: 8,766

    1971BB427
    Member
    from Oregon

    I posted the pictures of the aftermarket '55 Chevy side mount because I figured if you were asking about using a Hurst style front mount, then maybe you didn't have the skill level to fabricate mounts. But if you have the skill to fab a mount, then I wouldn't use the Hurst or the mounts I posted.
    Looking at the '55 Pontiac frame, it seems to me that fabricating side mounts to clear the steering box and suspension mounts would not be a difficult task. It looks like there's a lot more room than many people have to work with on some narrower frames. I'd put a pair of motor mounts on the engine, bolt a piece of round heavy wall pipe into the cross bolt, and lower the engine into the bay. Then level it up and tack weld some plate from the frame to the pipe sleeves. Pull the motor back out, and weld it all up solid. Shouldn't be much of a task at all.
     
  16. finn
    Joined: Jan 25, 2006
    Posts: 1,289

    finn
    Member

    Spend your time looking for a Pontiac engine. The SBC is stale (coming from someone who has one in a 36 Ford pickup).

    Pontiac made some good engines.
     
  17. Price out wheel cylinders, shoes, hardware, etc. for the stock front end.

    Pontiac engines aren't that hard to find, I've had enough I've even passed up on a few of them.
     
  18. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    4 wheel cylinders, front and rear shoes, hardware kits, adjusters, front and rear seals, brake hoses, rear axle bearings, = $212.37
     
  19. Nom
    Joined: Sep 6, 2009
    Posts: 9

    Nom
    Member

    It's a piece of cake. I got a 307 with a nice beefy cam in my '56 chieftain now with a fabricated bolt in th350 tranny mount. I'll eventually drop a pontiac motor in later down the road but it gets the job done! I didn't have to box my frame either. as long as you don't drive reckless like i did mine, then yeah boxing should be done, but i've taken them to hell and back unboxed and they held. Your frame mounts would be welded or bolted in front of the steering box. Right where your frame bends inward. I gotta dig in my external hard drive and find the pics of when i did them and send them your way so you know what you're in for. if i can't find em tonight i'll take some pics in the morning. and the true non-anal car buffs will love the fact you kept your gm car running with a gm motor.
     
  20. Bored Over
    Joined: Aug 9, 2008
    Posts: 76

    Bored Over
    Member

    Thanks for the pics, Nom. That's just what I was looking for.
     
  21. 1949SilverStreak
    Joined: Feb 25, 2013
    Posts: 21

    1949SilverStreak
    Member
    from Canada

    Word of caution if using Hurst mount like I did.

    When using the front mount the weight of the engine and tranny, and consequent tourque moments under load, are split between the front mount and the transmission mount.

    Any amount of power can potentially damage/crack your transmission case unless you make a third mount that bolts to the bellhousing (which there should be enough room)

    Had to do that on my 49 pontiac (different application, same principle) but that was because I had ~450hp.
     

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