HEI for 72 Skylark

Discussion in 'Sparky's corner' started by 71SkylarkConv, Aug 24, 2020.

  1. 71SkylarkConv

    71SkylarkConv Roll Tide

    I want to replace the points type distributor on my 350 with a GM HEI, What am I looking for?
    Any chance one from a 455 will work?
    Thanks, any info is appreciated.

    Art
     
  2. rkammer

    rkammer Gold Level Contributor

    The GM HEI will fall right in. If you use the factory cold air cleaner you probably will have to cut some out of the driver's side inlet as it will interfere with the HEI cap. You will also have to bring a full 12 volts to the HEI distributor instead of the resistive wire that goes to the points unit that came with it originally.
     
  3. flynbuick

    flynbuick Guest

    Is the 455 drive gear the same on a 455 and a 350?

    You could have an Lectric Limited or similar module put in your distributor. Have the advanced re-curved at the same time.
     
  4. Bens99gtp

    Bens99gtp Well-Known Member

    Bssicly the distributor its self swaps between 455 and 350....but the gear is 1 tooth different.......i believe the gear from your points dizzy will fit the hei though
     
  5. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    I don't like the big cap HEI distributors for a number of reasons, but they are a cheap alternative to points distributors, and parts are readily available for them. If you are going to buy one, get one from TA Performance that has a performance advance curve,

    http://www.taperformance.com/proddetail.asp?prod=TA_690

    If you get a junkyard HEI, any Buick 350 from 74-79, or 455 74-76 will work. The 455 distributor has a 13 tooth gear, so you will need to swap on a 14 tooth gear for the 350, and it will need to come from an HEI distributor, the points gears use a thinner roll pin (you could drill the gear hole larger). The production HEI's frequently used a lot of mechanical advance built in, which is why I recommend one from TA. The large cap makes them harder to install correctly. The cap can interfere and hit the front of the intake in some cases, hit the upper radiator hose, and the GS air cleaner. Just be aware of that.

    IMO, you are better off with a small cap distributor. TA sells an MSD ready to run clone,

    http://www.taperformance.com/proddetail.asp?prod=TA_724B

    You also have the option of rebuilding/recurving your distributor. Ken G. (techg8) can do that for you,

    http://v8buick.com/index.php?thread...available-at-everyday-performance-llc.316478/

    You can have him install a points replacement kit at the same time. This is the one I would recommend,

    https://www.lectriclimited.com/breakerless-se-electronic-ignition-conversion

    Then there is Dave Ray,

    www.davessmallbodyheis.com

    Dave can do an MSD trigger or HEI conversion using an external GM HEI module.
     
  6. 71SkylarkConv

    71SkylarkConv Roll Tide

    Thanks a lot. What a wealth of information!!

    Art
     
  7. john.schaefer77

    john.schaefer77 Well-Known Member

    Points gear and HEI have different sized roll pin holes
     
  8. 12lives

    12lives Control the controllable, let the rest go

    Since you have a Skylark your air cleaner should not be an issue with the big cap HEI. The nice thing about the big cap HEI is that parts are available almost anywhere and any shop can work on them. The parts are not the same across brands, but most places have or can get parts for any of them. Parts are easily found online. You will need to get HEI plug wires and change the feed wire to full time 12v. My 2 cents: Do yourself a favor and just get the TA HEI. It's well priced and and usually a drop in on a 350.
     
  9. 71SkylarkConv

    71SkylarkConv Roll Tide

    Thanks for all the info. I am leaning toward the big block HEI since I have one that I bought from Cole a couple of years ago. If I can find the 14 tooth gear I'll be on the way.

    Art
     
  10. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD" Staff Member

    You can take the one off your points distributor. You just need to drill the hole in the gear larger for the larger roll pin.

    Remember, that HEI has an unknown amount of mechanical advance. You can't just run whatever initial advance you want. It depends on the amount of mechanical advance in the distributor.
     

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