Hi Dan:
Dual points with single coil were standard equipment on all Chrysler
hemi-engines from 1951 - 1958.
John McEwen
>In a message dated 97-12-17 14:48:33 EST, CREICHLE@nsc.msmail.miami.edu
>writes:
>
>> Where did you get the idea that you need two coils to take advantage of a
>> mallory dual point distributor or that you could even hook this up if you
>so
>>
>> desired? The purpose of the dual points it to increase reliability and
>> accuracy of spark timing not to use two coils.
>
>Chris:
>
>I got the idea from the hundreds of dual point/dual coil installations I've
>seen in the last fourty years or so (mostly in the first half of those fourty
>years - advances in ignition technology have just about rendered them
>obsolete). Admittedly, never on an MG. As a matter of fact, I don't know how
>you would hook up a dual point system to use only one coil, or why. The
>statement I was responding to was "you get a hotter spark." From my knowledge,
>limited though it may be, I can tell you that you won't get a hotter spark
>from a single coil, no matter how many points you use. Reliability and
>accuracy are another story, and if you can hook up a single coil to use dual
>points, reliabilty and accuracy might well be improved.
>
>Always willing to learn, I would be interested in the connection scheme for
>dual points with one coil. Are they wired in parallel? In series? Is the
>purpose to share the switching load? I'm curious. Keeping in mind that the
>points open to fire the coil, both sets would have to be open at the same time
>if they were in parallel, so I can't think of any advantage to that, either
>from a reliability or accuracy standpoint. If it's just to share switching
>loads, a simple set of larger contact points would do that. If they were wired
>in series, then each one would operate exactly half the time as compared to a
>single point set. Is that the purpose? How would that improve reliabiliy and
>accuracy? It would, of course, double the life of the points, but you have to
>buy two of them, so what is the gain? Educate me!
>
>The last dual point/dual coil installation I've seen was on a Ford 302 powered
>TVR that a fellow brought to the local Townsend car show about five years ago.
>He had found an old dual point distributor at a flea market, and had installed
>it with dual coils. He didn't use it for performance gains, but, like me, he
>is an OF, and used it just for nostalgia sake. I was so impressed with the
>Ford engine in his car, that I decided then and there to put one in my TR6,
>but without dual coils.
>
>> With electronic ign. you
>> don't have to worry about burning the points so you can go for the higher
>> output coil and larger spark gap to produce a fatter spark which will ignite
>> the fuel more reliably providing easier starts, better fuel economy and
>> possibly a bit more power depending on how you set it up.
>
>I won't argue with that, but I still say a well set up stock system is
>adequate for normal street driving. Having said that, I must confess - I have
>a Crane/Allison electronic ignition, with a Lucas sport coil, in my TR6.
>Primarily for the "hey, look at that!" factor, and for the reduced tune-up
>schedule.
>
>> I am the master of
>> the runon sentence...
>
>My favorite kind of sentence!
>
>Dan Masters,
>Alcoa, TN
>
>'71 TR6---------3000mile/year driver, fully restored
>'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
> http://www.sky.net/~boballen/mg/Masters/
>'74 MGBGT---3000mile/year driver, original condition
>'68 MGBGT---organ donor for the '74
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