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L Head Hei

Discussion in 'Flat Fender Tech' started by garage gnome, Nov 16, 2020.

  1. Nov 16, 2020
    garage gnome

    garage gnome ECJ5 welder 2021 Sponsor 2020 Sponsor

    Western MA
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    I bought a summit racing sbc hei for $99. I figured “what the heck, this will be a fun experiment.” To my surprise, the shafts between the stock distributor and the sbc hei were the same diameter. I completely disassembled the hei and put the hosing on the lathe and started whittling away. Now it has the same dimensions as the stock distributor.

    [​IMG]

    It fits into the oil pump perfectly too.

    [​IMG]

    Now the only thing I’m stumped on is, converting it from an 8 cyl to a 4. I’m thinking I just remove every other point on these two stars for the magnetic pickup?

    [​IMG]

    [​IMG]
     
    blalp!, timgr, Fireball and 1 other person like this.
  2. Nov 16, 2020
    AKjeff

    AKjeff Member 2021 Sponsor 2020 Sponsor

    Carson Valley, NV
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    I dunno, but I'm going to watch and see what you find out.
     
  3. Nov 17, 2020
    73 cj5

    73 cj5 Not ready for the junkyard yet 2020 Sponsor

    Biloxi, Mississippi
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    That’s what I’d do. I have a Pontiac distributor set aside for this.
     
  4. Nov 17, 2020
    45es

    45es Member 2021 Sponsor 2020 Sponsor

    Naches, WA
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    I'm thinking you may want to try it as is. As is, it may function in a similar manner as a wasted spark ignition.
     
    Downs likes this.
  5. Nov 17, 2020
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor 2021 Sponsor 2020 Sponsor

    Medford Mass USA
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    I would look at 4-cylinder or even 6-cylinder HEI distributors to see what GM does. The principle is variable reluctance, where the field is disturbed by the changing magnetic permeability of the iron core, when the pointed core pieces are close and far.

    upload_2020-11-17_10-49-2.png

    This is from a 1980 Chevette - sure looks like the HEI pickup coil. I expect you need four points on the reluctor (shaft mounted) as well.
     
    Last edited: Nov 17, 2020
  6. Nov 17, 2020
    Siskiwit

    Siskiwit Member

    Northern Wisconsin
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    You have my undivided attention.
     
  7. Nov 18, 2020
    IRQVET

    IRQVET Bubbaification Exorcist

    Tallahassee, FL.
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    Getting my popcorn . . . :watch:
     
  8. Nov 18, 2020
    garage gnome

    garage gnome ECJ5 welder 2021 Sponsor 2020 Sponsor

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    I got the HEI installed and all hooked up. Ted fired right up and ran really well until I tried to rev him up. The mechanical advance doesn’t work. Upon further investigation, sbc distributors rotate the opposite way. :(

    [​IMG]
     
  9. Nov 18, 2020
    73 cj5

    73 cj5 Not ready for the junkyard yet 2020 Sponsor

    Biloxi, Mississippi
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    That's why I have a Pontiac distributor. :schooled:
     
  10. Nov 18, 2020
    Buildflycrash

    Buildflycrash Blind and Dirty 2022 Sponsor 2020 Sponsor

    Gulf Breeze FL...
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    That was worth every penny. since none were mine!
    Got a plan to flip something over?
     
  11. Nov 18, 2020
    Jw60

    Jw60 Member: Club Foot Dad Club. 2022 Sponsor 2021 Sponsor 2020 Sponsor

    Sedalia MO.
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    Waiting for the other captain....
     
  12. Nov 18, 2020
    Jw60

    Jw60 Member: Club Foot Dad Club. 2022 Sponsor 2021 Sponsor 2020 Sponsor

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    Do inline Chevy distributors rotate the same as a v8?
     
  13. Nov 19, 2020
    Fireball

    Fireball Well-Known Member 2022 Sponsor 2021 Sponsor 2020 Sponsor

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    You might be able to flip the cam and weights over. Of course, the vacuum advance will be pulling the wrong way too. Might need to weld the Chevy shaft to the bottom of a Pontiac HEI.
     
  14. Nov 19, 2020
    garage gnome

    garage gnome ECJ5 welder 2021 Sponsor 2020 Sponsor

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    I have a pontiac HEI I'm going to take a look at. Modifying the chevy one wasn't a total loss for me because the 55 chevy has HEI and this thing can be spare parts for it if I have to go back to the drawing board.
     
    masscj2a likes this.
  15. Nov 21, 2020
    blalp!

    blalp! Member 2022 Sponsor 2021 Sponsor 2020 Sponsor

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  16. Nov 21, 2020
    garage gnome

    garage gnome ECJ5 welder 2021 Sponsor 2020 Sponsor

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    The other hei I had turned out to be another sbc one. I ordered a cheap Pontiac one.
     
  17. Nov 26, 2020
    garage gnome

    garage gnome ECJ5 welder 2021 Sponsor 2020 Sponsor

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    The Pontiac hei did the trick! Works great!


    [​IMG]
    [​IMG]
     
    dozerjim, Jw60, Rich M. and 4 others like this.
  18. Nov 26, 2020
    AKjeff

    AKjeff Member 2021 Sponsor 2020 Sponsor

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    Nice.

    I was going to say, that's probably the newest tech on the jeep, then I saw the Weber.
     
  19. Nov 26, 2020
    CHUGALUG

    CHUGALUG Member

    Silverton, OR
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    If you want the Weber to work even better rotate it 90° so both runners are the same length With the carb barrels parallel to the runners this causes one runner to effectively be longer then the other causing an imbalance in the amount of fuel/air mixture available to be sucked into the combustion chamber. Granted to do it causes all sorts of throttle linkage PITA but it is an improvement.

    I spoke at length a while back with a guy who was doing exactly what you have done converting GM HEI to various older engines. On the 4cyl engines using a V8 distributor he said at higher rpm the unused spark signals can cause some spark jumping. I do not remember at what kind of rpm he said this might occur but should you find a problem you might look that direction.
     
  20. Nov 26, 2020
    Fireball

    Fireball Well-Known Member 2022 Sponsor 2021 Sponsor 2020 Sponsor

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    :bananatool:
     
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