Page 2 of 2 FirstFirst 12
Results 11 to 12 of 12
  1. #11
    Experienced Lancista tangmonster's Avatar
    Join Date
    Apr 2017
    Cape town ,South Africa

    Re: Electronic Ignition?

    at 6000rpm the distributor rotor is turning at 3000rpm

    For a dwell of 60 degrees ( degrees of rotation that coil is energized) the points only has 3.33ms to charge coil for each spark

    Question is with hot points what is the resistance of those points contact? It sure as heck won't be the sub 100mohms that modern Mosfet technology can provide.

    Is 3.3ms enough to charge coil up completely taking it's inductance and points resistance into account?

    Also How good is that spring on the points? does it even close quick enough to provide 3.3ms??

    In below graph points are not able to fully charge coil:

    at 1000rpm the distributor rotor is turning at 500rpm
    at 60 degree dwell that is the points gets close to 20ms to charge coil. That is a lot of wasted energy heating up coil and points.

    I am still running points. But I am quite interested to measure using oscilloscope the charging curves for interest.

    There are many other variables.

    even a simple system that has lower wasted energy limiting charge time and sub 100milli ohm resistance that will provide quicker coil charge time would be technically superior.

    How much it improves top end power I am not certain. But it should at very least help with cold running and "clean up" top end and provide increase in driveability.

  2. #12
    Master Lancista Racer's Avatar
    Join Date
    Sep 2015

    Re: Electronic Ignition?

    Quote Originally Posted by Fulvia-hf View Post
    When I developed the engine of my 1200Hf I found out that the stock ignition, having worked perfectly well on the stock engine, proved to be the Achilles heel on the new engine.
    The new engine with hairy cams, 42 Solexes and over 11:1 CR needed a substantially different advance curve. The 123 Tune provided all that and even if I do not like the look of this thing it proved to be one of the best modifications of all. It removed a stubborn flat spot and raised low down torque, lessened pinking and works as a rev limiter (cut out a 8000rpm). I believe max power on the dyno was the same as the stock ignition (point replaced with Pertronics) but the car became much more rideable. Oh, I have fitted the 123tune with programmable vacuum advance. Fulvia's never had this but carefully programmed this vacuum advance improves mileage somewhat.


    William, PM sent


Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts