1979 350 Buick head swap

Discussion in 'Small Block Tech' started by Al Baker, Feb 24, 2002.

  1. Al Baker

    Al Baker Member

    Ihave a 350 out of a 1978 Lasabre that is in good shape .I also have a set of heads off a siezed 1970 engine (350) .Can these heads be made to work on the 78 engine? I'm thinking of putting this combo and OD in my 84 OLDS wagon as the 307 is tired and a gas hog .I was also thinking of installing a Comp 252H cam for gas mileage .I realize this is no econo car but it sure is relible especially in the winter .In my trade(union M/W) I travel all over Canada packing my Tools and cloths so a truck is not an option .
    Any further ideas on this plan would be greatly appreciated .This is not a performance car just reliable .I hope that the 70's heads will up my compression to 8.5 or so .I don't want to touch the bottom end as it's still in good shape .
    Thanx 455 Z28
  2. Is that 78 350 a Buick engine? I didn't think Buick made their own anymore then...???
  3. buickdav

    buickdav Kris' other half.


    it has always been my understanding that all the 350's were the same. so i will say yes they will work i have a 70 and a 78/9(cant remember) that i am going to do this on for another regal. somewhere i heard that the only diff. was the valve sizes in the 350's. that and after 74'? the cap screw rods that are prefered. try looking over your heads side by side. maybe put the 78' head gasket on the 70 head. not sure here just trying to help.

    let me know how it turns out. like i said i too was about to try this.

  4. Darryl Roederer

    Darryl Roederer Life is good

    The last of the buick 350's

    I'v heard that canada got the "leftovers" after the USA market switched to the "corporate" crap.

    Anybody remember Lee C. ?
    80 Park Ave [canadian exportmodel] factory with 350 buick engine/T-400... Sweet combo! [BTW, Lee, where are you ???]

    Make sure it's really a buick 350 before you start. Not questioning your mechanical abilitys, but the stupid stuff GM did in the late 70's with engine brand swaping still puzzles me.

    All buick 350 heads use the same castings, and will swap with little trouble. The 252H cam is a really mild one and should work well in that combo. I'm beginning to like the low compression 350's personally. Just did a 71 for a friend, put a 262 Isky cam in it, factory cast 4V intake, dual exhaust and an HEI. Those were the only upgrades... Difference was night and day! I was quite impressed with the power, and the low compression lets it use lots of timing without ping, and on reg gas!

    While you've got the engine out of the car, replace all the gaskets,and the front and rear seals with modern neoprene ones. I personally would re-ring and bearing it. Not hard at all to do, and not very expensive if you can do it yourself... Cheap insurance in my opinion.

    What "overdrive" tranny do you have? Is it factory installed behind the buick? The Olds? or did you personally install?
    Reason I ask, being canada, and the leftover parts thing, just wondering if you have one of the "ultra rare" BOP 700-r4's.
    If you do have the 700, do you want to sell it?:laugh:

    Go with a Q-jet 4V. It will get better mileage believe it or not. Also, dual exhaust will help MPG and HP a lot. Buicks love to breath.

    Should make a nice and reliable combo, keep us updated:)
    BTW, 455 Z-28? I'll bet that's a hoot!
  5. Al Baker

    Al Baker Member

    350 Head swap

    Yes guys I'm doing the rering and bearing thing and no please doubt my ability as i'm just getting into this wrenching on cars thing .The engine is in fact a buick (oil filter out front) and the trany is an olds 200-R4 Ididn't know of the BOP700-r4 overdrive Thanx for ever thing
    have amost excelt week at work
    455 Z28
  6. Darryl Roederer

    Darryl Roederer Life is good

    B4 I forget...

    One more thing...

    The 70 heads you have, you can identify the 70's by the aluminum rockers. The 70's did have smaller chambers than any other year, so it should help bump up the CR.

    Make sure you are using 70 or later heads, as the 69 and earlier used a different oiling setup. Using 69 heads will require some changes be made... Not major changes, but just more trouble that could be avoided by later heads.

    Also, the 70 only aluminum rockers a little stronger and lighter than stamped ones used in all other years.

    Good luck!!!
  7. Mark Demko

    Mark Demko Well-Known Member

    I have 69 heads on a 78 350 block with no problems. What was weird tho was my original 71 block did not have the oil passages drilled for thru the head oiling, but the 78 long block I picked up did have the oil thru the head transfer holes:Do No: Hmm Mark
  8. Al Baker

    Al Baker Member

    78 Buick 350 Head swap

    Just one question ,how would you rate the reliability of the pre 70's rocker shaft set up as compared to the after 70's setup .I guess I'm Wondering how reliable the old setup is.Also will the push rods out of my 78 engine work in the old style rockers.Once again I can't thank all you guys enough for all the info

    Thanx Z28 Camaro
  9. Darryl Roederer

    Darryl Roederer Life is good

    In all the years I'v been doing this, I have never seen an aluminum rocker fail. I'v seen 1 stamped steel rocker fail [pushrod poped up thru the rocker] and 1 come loose, break the nylon button, walk off the valve, and bend the push-rod.

    The aluminum setup seems to "clatter" a little more than the steel. [just a very slight valve-train noise]

    I personally prefer the 70 "oil thru the push-rods" aluminum setup, as it just plain looks like a better engineered piece.

    All the 70-up pushrods are the same, you should have no problem there.

Share This Page