Register now to get rid of these ads!

overdrive and breakerless ignition

Discussion in 'The Hokey Ass Message Board' started by flatordead, Dec 20, 2013.

  1. What do I do with the wire that goes from the kick down switch to the ign coil terminal when I go breakerless (pertronix, MSD, unilite). Do I skip the kick down switch and just connect the governor direct to the solenoid?
     
  2. I think that is your power supply which comes from the ignition switch, keep it hooked to the coil.
     
  3. No Its not battery side of the coil, its on the ditributer side.
     

    Attached Files:

  4. Check with the ignition manufacturer to make sure it won't damage the electronics if you connect the kickdown relay to the coil. You can delete the relay, but you will lose the kickdown function and won't be able to 'shift' out of overdrive unless the governor calls for it, i.e. at speeds below about 22 MPH.
     
    Last edited: Dec 20, 2013
    Register now to get rid of these ads!

  5. R Pope
    Joined: Jan 23, 2006
    Posts: 3,310

    R Pope
    Member

    That wire momentarily "shorts out" the points, releasing the engine torque so the OD can shift down. Not sure what that will do to electronic ignition.
     
  6. 325w
    Joined: Feb 18, 2008
    Posts: 5,209

    325w
    ALLIANCE MEMBER
    from texas

    Hope GMC Bubba comes in on this. I would like to know also..
     
  7. Pertronix has a grate Tec Support. If your using there product you owe it to yourself to go direct to them.
    The Wizzard
     
  8. I believe we (PerTronix) handle this the same way we do boats that have a shift interrupt - send me an email dlindfors@pertronix.com and I will talk to the engineer on Monday.
     
    The ideaman likes this.
  9. Jack E/NJ
    Joined: Mar 5, 2011
    Posts: 562

    Jack E/NJ
    Member
    from NJ

    R Pope>>>That wire momentarily "shorts out" the points, releasing the engine torque so the OD can shift down. Not sure what that will do to electronic ignition.>>>

    If that's all it does, it shouldn't do anything as the electronic ignition also shorts to ground (intermittently) just like the points. If anything, maybe more stress on the coil depending on how long the kickdown takes.

    Jack E/NJ
     
  10. 46Ford
    Joined: Jul 7, 2006
    Posts: 80

    46Ford
    Member

    I don't know what solution Hotroddon has in mind, but I have been looking at doing a 4 +1 OD with a Saginaw 4 speed. I have an HEI, so I would be in the same boat as the OP.

    I thought about running the power for the distributor through a normally closed relay and wiring the coil on the relay to the kickdown switch. That would kill the power to the ignition when the pedal was down and accomplish the same thing as grounding the coil on a point type distributor.
     
  11. Jack E/NJ
    Joined: Mar 5, 2011
    Posts: 562

    Jack E/NJ
    Member
    from NJ

    That'd work good too.

    Jack E/NJ
     
  12. It fried the Pertronix in my Edsel.

    Went back to the points and all has been fine for 2 years now.

    Just sayin :rolleyes:

    Oldmics
     
  13. PTO
    Joined: Sep 25, 2011
    Posts: 114

    PTO
    Member
    from CA

    Oldmics has a good point. If you buy good NOS points, they will work great. Unless your trying to upgrade to the newer HEI distributor. I have had no experience with those.

    Had pertronix. They seem good for a while, but go bad. That being said, I have had several shitty points that never wanted to work. My experience says to find a good clean set of old NOS points.

    The new ones they make today are practically worthless.
     
  14. tjet
    Joined: Mar 16, 2009
    Posts: 1,271

    tjet
    Member
    1. Early Hemi Tech

    Does the wire short to ground, or does it open. I can't tell in the diagram.
     
  15. tjet
    Joined: Mar 16, 2009
    Posts: 1,271

    tjet
    Member
    1. Early Hemi Tech

    You can still get quality points from Napa.
    Here are some Napa Echlin p/n's for a GM, lightest to heaviest spring tension:
    .
    • CS86 - Standard Duty
    • CS786 - Heavy Duty
    • CS786P - Vented
    • CS89 - High Performance (transistorized ignition possibly)
    • CS7860 - High Performance
    • CS7860C - Racing Only

    I have a set of the HD, HP, & Racing, but I've yet to float the 786 HD ones (have taken it to 6000 RPM) I never tried the standard tension model or the vented one (marine?).
    Also, i think p/n CS89 is for the optional RPO K66 T.I. ignition systems (W-30 olds, L-88 vette, etc) Not sure what the diff would be for that. Maybe contact material?

    For a condenser I use p/n RR175

    http://www.napaonline.com/Catalog/R...ord/Nty-1/N-599001 101971 50012 2012030/Nao-0
     
    Last edited: Dec 21, 2013
  16. R Pope
    Joined: Jan 23, 2006
    Posts: 3,310

    R Pope
    Member

    As I said, it's a "momentary" ground. It only grounds for an instant, each time the button is depressed. It just has to release the torque long enough for the OD to kick out.
    I didn't use the kickdown switch on my Chevy, just an on-off switch on the shifter. Flip the switch, then let off the gas and punch it again as quick as possible. Worked great!
     
  17. Cosmo49
    Joined: Jan 15, 2007
    Posts: 1,126

    Cosmo49
    Member

    Yes, that is what I have done (skipped the kick down arrangement) on a daily driver only vehicle the last 15 years. I have a convenient dash switch to switch OD on/off and also have a 'reminder light' to tell me that I am in OD.

    Cosmo
     
  18. Jack E/NJ
    Joined: Mar 5, 2011
    Posts: 562

    Jack E/NJ
    Member
    from NJ

    R Pope>>>I didn't use the kickdown switch on my Chevy, just an on-off switch on the shifter>>>

    Cosmo>>>skipped the kick down arrangement)>>>I have a convenient dash switch>>>


    The simplest ways, the best ways!

    Jack E/NJ
     
  19. BLUDICE
    Joined: Jun 23, 2006
    Posts: 1,471

    BLUDICE
    Member

    NAPA points in mine for over 2 years - haven't touch them and car runs just fine ( btw has OD too )
     
  20. CJS
    Joined: Dec 1, 2010
    Posts: 88

    CJS
    Member

    The wire from the solenoid to the coil is using the points as a momentary ground just as the coil is. The solenoid would get to hot if it used a direct constant ground. The engine does not momentarily shut off but runs without a hesitation as the points still ground the primary voltage. If the engine shut off and on you would be buying a lot of mufflers. I am thinking the points are used for ground because the solenoid was likely the same as used for 6 volt systems and 12+ voltage would fry the solenoid. Likely an ignition resister dropping the voltage to around 9 volts would work in that wire to a common ground.
     
  21. Jack E/NJ
    Joined: Mar 5, 2011
    Posts: 562

    Jack E/NJ
    Member
    from NJ

    CJS>>>The wire from the solenoid to the coil is using the points as a momentary ground just as the coil is.>>>

    Well, if that's the way it works then I can see why an electronic ignition could get overloaded if the trip current for the overdrive solenoid is too high. Trip currents should typically be way less than an amp so there shouldn't be a problem unless the electronic ignition is poorly designed.

    Jack E/NJ
     
  22. CJS
    Joined: Dec 1, 2010
    Posts: 88

    CJS
    Member

    Jack, I agree that hooking the wire to the neg post on the coil shouldn't be a problem. I am trying to suggest another way to ground the overdrive solenoid in order to keep the smoke inside the electronic ignition module . jmo
     
  23. OK, I just talked to one of our Electrical Engineer on this.
    With a Negative Ground system, the PerTronix Ignitor modules don't have a problem with the 1950's Ford Style Overdrive switch that grounds to coil negative for an instant during O/D switching.
    If the car is still Positive Ground, then we do recommend putting a 7 Ohm, 5 watt Diode in the wire from the switch to coil negative.
    Using them in this way will not void warranty and should not cause any issues at all.

    Other brands of Overdrive switching, like Packard and International for instance are different and require different installation procedure.
     
    Last edited: Apr 25, 2016
  24. frosty49
    Joined: Apr 23, 2012
    Posts: 36

    frosty49
    Member

    I have Mallory unilite in my 49 Ford with flathead and over drive. You must use the wire to the coil or it will not downshift right. I have been using mine wired the original way a long time with no problems
     
  25. PTO
    Joined: Sep 25, 2011
    Posts: 114

    PTO
    Member
    from CA

    I have had those, and still bad. The last set I used was from napa. They burned shut. The actual points on the points were made from shitty metal, so they didn't last. The california heat may have helped. Were used on a 428.
     

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.