Adjusting 308 Distributor Points With A 2x4 | FerrariChat

Adjusting 308 Distributor Points With A 2x4

Discussion in 'Technical Q&A' started by donaldh2o, Sep 28, 2006.

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  1. donaldh2o

    donaldh2o Karting

    Nov 10, 2003
    143
    Irvine CA
    Full Name:
    Don
    #1 donaldh2o, Sep 28, 2006
    Last edited by a moderator: Sep 7, 2017
    Don't have a "Synchrograph Distributor Machine" so I had to make my own bench tester for my '76 308 distributors (single points). After I set the gap on both distributors I threw out the tester. Sorry no pictures, so use your imagination.

    It started with a 2x4 with a hole in the center (for the distributor shaft) then three 1" x 1/4" lag bolts secured the distributor to the 2x4.

    Next I used an old Panasonic TV power adapter (pluggged into 120VAC) that provided +12v and ground to the distributor. Clipped off the mini plug and attached alligator clips to the adapter wires. The adapter provided 300ma to the bench tester - an ideal current source. (Does not need to be exactly +12v - any low voltage source will be fine)

    The +12v alligator clip is attached to the hot connector on the side of the distributor (same as the capacitor) and the ground alligator clip is attached to any ground place on the distributor frame - a lag bolt is fine.

    Now attached one DC multimeter leader to the 12v and the other leader to the ground and the tester was ready to go.

    Shown is a 360' dial which was sized (Corel Paint Brush) to be the exact diameter as the top of the distributor. This donut was cut out and placed on top of the distributor - the notch at 0' was aligned with the red dot on the face of the distributor. Once aligned, the template donut was hot glued to the top of the distributor.

    The distributor rotor is left on the distributor shaft as part of the tester.

    Now using the meter and rotating the rotor clockwise from 0', the points should be open for 56' then close for 34', alternating, this way all around the 360' of the rotation of the rotor. If the points don't open and close as exactly as shown on the template the point gap was adjusted several times until the distributor exactly matched the template. Open=12v and Close=0v, meaning the adapter can get pretty warm if its left "close" for a length of time.

    The points have been working ever since.
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  2. gerritv

    gerritv Formula 3

    Jun 18, 2001
    1,400
    St Catharines
    Full Name:
    Gerrit
    Suitable choice of technology to match the age of the car :)

    Gerrit
     
  3. Artvonne

    Artvonne F1 Veteran

    Oct 29, 2004
    5,379
    NWA
    Full Name:
    Paul
    Have you checked your dwell with a meter with the car running?

    I didnt have a distributor machine until a few weeks ago, I am waiting until the end of October when I begin tearing the car down to use it. But this summer when I was trying to make her go, I did something very simular in that I set the distributor over the center of a metal degree wheel, and used the continuity setting on my meter to indicate open and close of the points. But when I ran the distributors on the car, the dwell was off a ways, reading ap around 50 degrees IIRC. Still not having a machine, I chucked them up in my lathe, set up a coil powered off a car battery, and spun them up, letting the coil wire spark to ground. This way I could read dynamic dwell under load. You could also do this with a drill motor. All the big machines do is to have variable speed so you can see how your mechanical advance is working. Dont forget to reset your timing at 5000 RPM to the max adavance marks. Thats THE most important setting.

    I still prefer points, but the idea of having one distributor run both coils and then having that same coil take care of the advance is intriguing. I am going to look at the possibility of running a second points set in one distributor simular to the way the Pertronics units are installed.

    Great post, I like discussions like these. Keeping it simple is what will keep these cars out on the road instead of rotting away in a garage.
     
  4. jhsalah

    jhsalah Formula 3

    Apr 10, 2006
    2,404
    Philadelphia, PA
    Full Name:
    Jawad
    You guys never cease amaze me with your ingenuity.

    Though I must admit, upon first reading the title of this thread, I thought someone had gotten so frustrated working on their car that they'd taken a 2x4 to it :D (That would have been funnier, at any rate, though not all that "helpful").

    J.
     
  5. 4Webers

    4Webers Formula Junior

    Nov 12, 2003
    276
    Texas
    Full Name:
    Darrell
    there have been more than one time when I have thought of just that...
     
  6. robertgarven

    robertgarven F1 Veteran
    Owner

    Feb 24, 2002
    5,269
    Ventura, California
    Full Name:
    Robert Garven
    #6 robertgarven, Sep 28, 2006
    Last edited by a moderator: Sep 7, 2017
  7. thecarreaper

    thecarreaper F1 World Champ
    Silver Subscribed

    Sep 30, 2003
    17,564
    Savannah
    i hate points.


    i feel better now.... :)



    VERY cool idea though !
     
  8. Mike Florio

    Mike Florio Formula Junior

    Jun 19, 2003
    592
    NW Rural Nevada
    Full Name:
    Mike Florio
    #8 Mike Florio, Sep 29, 2006
    Last edited by a moderator: Sep 7, 2017
    Angle iron frame, sewing machine motor, magnets glued to a 5.25 disk drive platter with a reed relay pickup for RPM sensing, plastic hose coupling to shaft, two plastic see-thru protractors glued together... a thing of beauty
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  9. ATSAaron

    ATSAaron Formula 3
    Silver Subscribed

    Jun 1, 2004
    1,120
    Shady Shores, TX
    Full Name:
    Aaron Bunch
    Is there a place that I can send my distributors to to have the points adjusted properly for a fee?

    Aaron
     
  10. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,913
    USA

    Okay, thread hijack...ROB, YOU HAVE THE COOLEST GARAGE!! (or should I say "Ferrari shrine"?) ;)
     

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