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Discussion Starter · #1 ·
Just wondering with all the older points cars out there, does it take a hotter spark to ignite unleaded fuels or just an upgrade to electronic is just a better idea for a better spark and complete burn of fuel. If I was running points on my 289. I would find that the change to Pertronix or MSD will give me a better idle quality because of that. Or should one be able to have the car operate just the same as leaded fuels.

Thanks

Greg
 

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Wow, this is going to be a good one. :)

No it does not take a hotter spark. You can run points on modern engines if they were physically able to do the same things that modern ignition coils that sit over each plug can do, but they can't.

That said, getting a complete burn is hard to do if you don't have the fuel atomized, or any of several other factors. And we're NOT burning all of our fuel anyway (In ANY car modern nor vintage), the design of our engines isn't efficient enough to burn it all.

But points will burn as completely as pertronix if they're tuned right, but the MSD has Multiple sparks and I reckon that since once they are added to an already decent system make a noticeable difference, which means that they make the burn more efficient, but not by being a hotter spark, but by purposefully adding more sparks per ignition sequence, which gives a larger combustion front due to the actual turbulence going on in the chamber during the compression stroke.


I relayed what I could with my limited performance related vocabulary. Someone else can likely tell it all in a single sentence, but I like trying to explain my thoughts.
 

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Points wear out and need adjustment. Electronic systems could last the life of the vehicle. See the difference?
 

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Multible sparks and fancy coil windings are a crutch for the fact more duration of spark is needed. Thats the amout of time the coil has to build and length of time to dilver the spark. Jumping a bunch of gaps dosent help either. Most multiple spark systems also drop the multable sparks after about 3000 RPM as it cant keep up after that.
Do to emissions, need of a more complete burn multiple coil packs were adoped, later coil on plug. Most coil on plug systems each strike can be programed individually to strike at the presice moment its needed.
The programable systems have an advantage over mechanical systems for several reasons.
Todays fuel also requires as much initial advance as possible and less mechanical compaired to old fuel.
If I remember correctly it has always taken about 40,000 volts to fire the mixture. Some cylinders might require more or less depending on things like mixture distribution, cylinder temperature, in the same engine.
 

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Multible sparks and fancy coil windings are a crutch for the fact more duration of spark is needed. Thats the amout of time the coil has to build and length of time to dilver the spark. Jumping a bunch of gaps dosent help either. Most multiple spark systems also drop the multable sparks after about 3000 RPM as it cant keep up after that.
Do to emissions, need of a more complete burn multiple coil packs were adoped, later coil on plug. Most coil on plug systems each strike can be programed individually to strike at the presice moment its needed.
The programable systems have an advantage over mechanical systems for several reasons.
Todays fuel also requires as much initial advance as possible and less mechanical compaired to old fuel.
If I remember correctly it has always taken about 40,000 volts to fire the mixture. Some cylinders might require more or less depending on things like mixture distribution, cylinder temperature, in the same engine.
6,000 volts to firer the plug , little more for high loads on a N/A
 

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A hotter ignition was designed to burn leaner fuel mixtures (whether lead based or not) beginning in the early seventies and leading up to EFI today.

Points are archaic, although they can be used to fire say an MSD CD. But why? They wear and cause erratic signals.
 

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I replace my plugs every year or every 20,000 miles. My points operated ignition systems in my vehicles run fantastically. Nuff said. Hell man they ran points in Nascar in the fastest cars in the world in the 1960's....

You don't think they're good enough to run in a car you're building today, simply don't run them. :)
 

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Guess I was thinking more about a good coil's output.
Takes a bit over 12,000 volts to fire a plug depends on gap also small less larger more.
OEM coil in general puts out 26000 volts and craps out around 5000 RPM.
A old school HP coil would put out mabe 48000 V and crap out around 3500 RPM.
Around 7800 RPM voltage to fire a plug starts rising above 12000V up to about 28000V by 9000 RPM.
A good HP coil might put out 38000V AND START TO DROP OFF around 6800 RPM then around 9000 RPM break even with the amout required to fire the plug about 28000V.
 

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Guess I was thinking more about a good coil's output.
Takes a bit over 12,000 volts to fire a plug depends on gap also small less larger more.
OEM coil in general puts out 26000 volts and craps out around 5000 RPM.
A old school HP coil would put out mabe 48000 V and crap out around 3500 RPM.
Around 7800 RPM voltage to fire a plug starts rising above 12000V up to about 28000V by 9000 RPM.
A good HP coil might put out 38000V AND START TO DROP OFF around 6800 RPM then around 9000 RPM break even with the amout required to fire the plug about 28000V.
if you say so ..... But
 

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Discussion Starter · #12 ·
Good info all. Just a thought about my MSD rotor connection on the top that looks like it is ready to melt off. And then I have my old distributor out of the 289 , that has a Pertronix III and the rotor connection has a little tack mark on it. Only asked because I was informed about how they went that way with lean conditions, hotter spark and unleaded fuels to get emissions down. Thanks a bunch and as FE stated, those points in the old cars sure went fast. :)


Cheers

Greg
 

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Good info all. Just a thought about my MSD rotor connection on the top that looks like it is ready to melt off. And then I have my old distributor out of the 289 , that has a Pertronix III and the rotor connection has a little tack mark on it. Only asked because I was informed about how they went that way with lean conditions, hotter spark and unleaded fuels to get emissions down. Thanks a bunch and as FE stated, those points in the old cars sure went fast. :)


Cheers

Greg
On most electronic ignitions (think DURASPARK), a spot of dielectric gel is put on the rotor point to prevent arcing and subsequent burning.

The main reason for a hotter ignition was of course leaner fuel mixtures required to comply with emission regulations. They would have never done it on their own. Not only is the spark hotter, but is shot across a wider gap making complete burn more possible.

FORD went to Transistorized Ignition in 1963 for HI-PO reasons and that points are not reliable above certain RPM's..
 

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MSD snall caps and large caps the carbon center is fixed. The large cap center terminal with carbon can be replaced for around 10.00. The small cap the whole cap has to be replaced. The tension on the spring in the center of the rotor is important on the MSD.

The OEM Ford style large caps the carbon has a spring backing it up Dont remember if the rotor does would have to dig one out.
 

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On most electronic ignitions (think DURASPARK), a spot of dielectric gel is put on the rotor point to prevent arcing and subsequent burning.

The main reason for a hotter ignition was of course leaner fuel mixtures required to comply with emission regulations. They would have never done it on their own. Not only is the spark hotter, but is shot across a wider gap making complete burn more possible.

FORD went to Transistorized Ignition in 1963 for HI-PO reasons and that points are not reliable above certain RPM's..
klut the T/I ign. was also found on trucks
How does it work ? never new Ford had the T/I ing.
plus what is the rpm that points become unreliable ?
 

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Think it was around 68 or 69 chrys went eletronic. There point dizzys were sloppy. Best thing to do with thier dual points was to remove one set of points.
Ford went pointless a bit later.

Point dizzys could hit up in the 9K range with some changes in point spring pressure.
My favorite dual points back then were the double life Mallorys. One set of points ran half the engine the other set the other half. Kinda like a dual plane intake.
 

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Think it was around 68 or 69 chrys went eletronic. There point dizzys were sloppy. Best thing to do with thier dual points was to remove one set of points.
Ford went pointless a bit later.

Point dizzys could hit up in the 9K range with some changes in point spring pressure.
My favorite dual points back then were the double life Mallorys. One set of points ran half the engine the other set the other half. Kinda like a dual plane intake.
yes they could hit 9K rpm . I'd turn Accel dual to 8800 rpm , and with their 35535 box , spark is as hot as MSD 6

you saved the klutz from answering about something he doesnt know about

KLUTS STILL GOT THE t/i QUESTION
 

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OK smart men, your sarcastic banter has you half-way there, now which of you can tell us why KULTULZ was correct and why basic point systems are not good at high rpm? Then why dual-point systems were developed? Then further tell us why the electronic ignitions are yet better? That's 3 explanations of 3 different reasons. In your attempt to torture someone trying to help (whether they were right or wrong), you have won the chance to explain the WHY part and show you really know what's going on, and not just half the story. Go ahead... who's first?

David

PS: Any reply that is not a set of valid answers is considered a useless reply, an attempt to avoid answering, and indication that you don't really know. Therefore an apology is in-order to everyone who had to read that sarcastic crap including the OP. Bitches. :frown:
 

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OK smart men, your sarcastic banter has you half-way there, now which of you can tell us why KULTULZ was correct and why basic point systems are not good at high rpm? Then why dual-point systems were developed? Then further tell us why the electronic ignitions are yet better? That's 3 explanations of 3 different reasons. In your attempt to torture someone trying to help (whether they were right or wrong), you have won the chance to explain the WHY part and show you really know what's going on, and not just half the story. Go ahead... who's first?

David

PS: Any reply that is not a set of valid answers is considered a useless reply, an attempt to avoid answering, and indication that you don't really know. Therefore an apology is in-order to everyone who had to read that sarcastic crap including the OP. Bitches. :frown:
just one simple answer . for those that can't understand the answer , to bad .

Because points have been run to 9K rpm .
there is very few here that can run that rpm
every thing has a limit , just saying its got a limit doesn't cut it

don't feel bad that you hav'nt been there , you shoulnt have ask the question .

Oh , btw you ever ask quality control if a snap Gage is a presision tool ?

why is a different system better ? stick to the subject is better .
Then why is a diesel better ? might as well get off subject then .
 
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