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456M

Discussion in 'Technical Q&A' started by Gordy1953, Feb 5, 2025.

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  1. Gordy1953

    Gordy1953 Rookie

    Feb 5, 2025
    9
    I have an early sixties Ferrari; it now has a late model 456M 65-degree V12 engine six down draft Weber's etc
    I plan on adapting a Jaguar V12 distributor coming off the back of the right-hand cam shaft
    Actually, i already made up this configuration with and early V12 points distributor not knowing that the 456M fires 6 cylinders at 65 degrees and 6 cylinders at 55 only to find out that only some of the cylinders fired Durrrr
    Now the Jag fires at 60 degrees as does a Lamborghini has anyone out there any suggestions how I can make this Jag dist work I may have to design a new cam/reluctor and somehow build a new cap or modify the Jag one. Two six-cylinder distributors will not work either they are out of phase
    This is an odd firing V12
     
  2. wmuno

    wmuno Formula Junior
    Silver Subscribed

    Dec 24, 2007
    522
    Wilmette, Illinois
    Full Name:
    Bill Muno
    It appears you need to go with two 6-cylinder distributors. This would allow you to compensate for the different timing of each bank.
     
  3. Gordy1953

    Gordy1953 Rookie

    Feb 5, 2025
    9
    Here is what I came up with after carefully rotating engine with a degree wheel attach to crank and noting each and every cylinder at TDC
    At then end of day I found that 6 of the cylinders are at 65 degrees and 6 are at 55 degrees
    Example a 60 degree V12 you take 360 degrees divided by 60 and you get 6 hence the point distributor I have has a 6 lobe cam with two sets of points in other words on a complete rotation of distributor both sets of points open and close 12 times
    The Jag distributor I also have is a magnetic with a 12 point reluctor/cam
    Hear is my theory 360 divided by 65 equals 5.54 and 360 divided by 55 equals 6.55 now does one need a special reluctor/cam made and along with a distributor cap with off set terminals
    I feel the two x 6 cylinder distributors will not work no different than my Jag one
     
  4. Gordy1953

    Gordy1953 Rookie

    Feb 5, 2025
    9
    Here is what I came up with after carefully rotating engine with a degree wheel attach to crank and noting each and every cylinder at TDC
    At then end of day I found that 6 of the cylinders are at 65 degrees and 6 are at 55 degrees
    Example a 60 degree V12 you take 360 degrees divided by 60 and you get 6 hence the point distributor I have has a 6 lobe cam with two sets of points in other words on a complete rotation of distributor both sets of points open and close 12 times
    The Jag distributor I also have is a magnetic with a 12 point reluctor/cam
    Hear is my theory 360 divided by 65 equals 5.54 and 360 divided by 55 equals 6.55 now does one need a special reluctor/cam made and along with a distributor cap with off set terminals
    I feel the two x 6 cylinder distributors will not work no different than my Jag one
     
  5. wmuno

    wmuno Formula Junior
    Silver Subscribed

    Dec 24, 2007
    522
    Wilmette, Illinois
    Full Name:
    Bill Muno
    You stated that a 12 cylinder distributor won’t work. That being the case, the only other option is to try to make two 6 cylinder distributors work. If that is not possible for your application, then you have to use the original ECM and coils that were on the engine. Not exactly a vintage look.
     
  6. Aerosurfer

    Aerosurfer Formula 3
    Silver Subscribed

    Nov 21, 2020
    1,887
    Indianapolis
    Full Name:
    Nick
    Auraraptor likes this.

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