Who has the best coil?

[pcf_mark]

I took a direct shock from the MSD while checking for dead cylinders and while it was unpleasant it was not brutal. I think my coil (MSD blaster2) is pooping out or was never any good. Anyone know of some real test or comparision of coils?

I was thinking about usign the Ford e-coil which is hot and cheap according to some sites.

 

[69427]

I took a direct shock from the MSD while checking for dead cylinders and while it was unpleasant it was not brutal. I think my coil (MSD blaster2) is pooping out or was never any good. Anyone know of some real test or comparision of coils?

I was thinking about usign the Ford e-coil which is hot and cheap according to some sites.

There's not an easy answer to that question. Regarding the shock you got, remember, the manufacturers (both OEM and aftermarket) know ahead of time that a percentage of the users/purchasers are going to accidentally get shocked. They purposely have to limit the energy in the system to keep from killing or seriously injuring their customers. Dead customers are bad publicity, and rarely purchase their products again.
The real test of a coil involves measuring the inductance (and resistance), along with the amount of current that the control module regulates, or how much voltage/energy that the CD unit contains. Given that you're using a CD unit, remember that the energy in the ignition system is determined by the energy stored in the CD storage capacitor (which is then transfered to the coil). Quite often the voltage in the storage capacitor is mentioned in advertising or discussions, but the energy in the capacitor (due to its capacitance) is an important item, too.
Breaking it down, changing coils in an inductive system will change the energy in the system, and how it is distributed over the RPM range, but it still takes some instrumented measurements to determine if the energy level went up or down. In a CD system, outside of getting in and modifying the voltage or capacitance of the storage capacitor (which changes the energy level), I'm trying to get a good handle on what the (practical energy delivery) effects of changing the coil would be. From a technical aspect, I'd be interested in seeing what some of the sites you mention are seeing when swapping coils in a CD type system.

 

[pcf_mark]

Assuming the CD is a fixed component then changing only the coil could help me in a few areas I think. I am working on this as I and would like anyone to chime in!

1) If a different coil had a higher number of turns this would increase the output proportionally. More turns increases the field so when broken the spark has more energy.

2) If a different coil has a better heat sink (more liquid material, better liquid material and/or external heat sink for the fluid to transfer the heat to) this coil could produce more spark under varying conditions. In my case the coil is in the stock location and generally coil but my engine compartment gets stupid hot.

3) Could there be some difference in the quality of the wire used in the coil that could result in more spark energy?

Researching this has been very annoying because no one compares them on the same scale. What I can tell you is any OEM part (Ford or GM) is going to be better made than almost anything aftermarket and have a very long life. The MSD Blaster 2 I have seems to have a 50/50 satisfaction/disatisfaction ratio...

I have had an MSD shock me so bad I almost needed to change my pants so I was "shocked" when I got off so easy!

 

[mrvette]

Assuming the CD is a fixed component then changing only the coil could help me in a few areas I think. I am working on this as I and would like anyone to chime in!

1) If a different coil had a higher number of turns this would increase the output proportionally. More turns increases the field so when broken the spark has more energy.

2) If a different coil has a better heat sink (more liquid material, better liquid material and/or external heat sink for the fluid to transfer the heat to) this coil could produce more spark under varying conditions. In my case the coil is in the stock location and generally coil but my engine compartment gets stupid hot.

3) Could there be some difference in the quality of the wire used in the coil that could result in more spark energy?

Researching this has been very annoying because no one compares them on the same scale. What I can tell you is any OEM part (Ford or GM) is going to be better made than almost anything aftermarket and have a very long life. The MSD Blaster 2 I have seems to have a 50/50 satisfaction/disatisfaction ratio...

I have had an MSD shock me so bad I almost needed to change my pants so I was "shocked" when I got off so easy!

Decades ago a friend of dubious distinction who had a bastard vette of a '61 front and '58 rear, he grabbed a plug wire not ONCE and got knock back in the bushes, but got up again and did it TWICE.....:flash:

I think a stock HEI is about best you can do for reliability, and at that, solder the coil connections on the terminals, where the Red/wh-yel wires are crimped...

your comment about turns on the coil is not necessarily the end of the story, there are obviously two set of windings on there, and the power of a breaker point is limited due to point life, there is a series resistor in there to limit the current, primarily to keep it running when the dwell changes due to wear or miss adjustment, to increase the number of turns on the secondary does not necessarily do much it will increase the VOLTAGE, but there is only so much power in the coil frame, that stored magnetic field has X amount of power in it, so the increase of voltage will mean a decrease in amps available...

An HEI for instance has all the dwell shit programed into the chip driving the coil, so even the series resistor is not there....much tighter operating parameters....

IMO, copper wire is copper wire, and so for any given gauge the resistance is the same, obviously inductance changes with the magnetic coupling and the way it's wound on what style of iron core....then the iron core composition can be a great effect on it too...

Lots of happy horse shit going on in that 'field'....so to speak, I used to do a fair amount of work in it, first as a TV man, then working in a small company making walk through metal detectors, and treasure finding stuff, like Mel Fishers gear on the Atocha .....our gear worked on pulse field, not RF...all switch like an ignition system, metals react very weirdly to pulse field electronics, not what we would expect at ALL.....

 

[TimAT]

A very long time ago I hooked a Sun Tune-up machine to a car that had one of those new (at the time) Accel Super-Coils on it. IT was hot enough that touching the Sun machine would light you up. Wasn't the machine, no problems with any other car.

 

[69427]

Guys, ya gotta remember, a coil does not generate energy. It merely stores it and/or transfers it from the primary to the secondary. In an inductive system (points, HEI, etc) the energy comes from the amount of current that is flowing through the particular amount of inductance that comprises the primary windings. (The secondary windings only bump up the voltage. They do not bump up the energy.) In a CD unit, the energy is determined by how big the module storage capacitor is, and how much voltage is in it. (Analogy: A big air tank with 100 psi has more "energy" in it than a small tank with 75 psi.)
You can work around the edges to increase the efficiency of the energy transfer from the storage capacitor to the secondary windings, but ya gotta work with the laws of physics.

 

[pcf_mark]

Here is how I think it works and it is a little contray to what has been stated. I am not saying I am right, only trying to get to the bottom of it. Smart guys here so I feel safe banty around ideas.

We put energy into the coil over a fixed period of time (dwell) into the windings of the outer coil that generates a magnetic field in the inner coil. When time is up (point open etc) the power is removed and the magnetic field rapidly collapses. The rapidly collapsing field induces the spark in the inner windings.

I think the time of putting the energy and taking it out represents the energy differential. It is all the same energy just the speed at which is avaiable changes in the coil. The ignition (points, CDI etc) are all switching mechanisms to control the start and stop of energy. MSDs big woo hoo is that it can rapidly control the coil and get several hits within a cycle versus one hit like points. The second feature (I think) with MSD or any CD system is the capacitor is a big, fast acting battery that can re-supply the coil with energy very quickly.

All that being said I have energy going in from some controlled source like and MSD, it then collapses a field and a spark happens. Is anyone making a coil that can more effectively make use of this energy? Better wire, better cooling, two inner coils, go fast paint etc?

 

[mrvette]

Here is how I think it works and it is a little contray to what has been stated. I am not saying I am right, only trying to get to the bottom of it. Smart guys here so I feel safe banty around ideas.

We put energy into the coil over a fixed period of time (dwell) into the windings of the outer coil that generates a magnetic field in the inner coil. When time is up (point open etc) the power is removed and the magnetic field rapidly collapses. The rapidly collapsing field induces the spark in the inner windings.

I think the time of putting the energy and taking it out represents the energy differential. It is all the same energy just the speed at which is avaiable changes in the coil. The ignition (points, CDI etc) are all switching mechanisms to control the start and stop of energy. MSDs big woo hoo is that it can rapidly control the coil and get several hits within a cycle versus one hit like points. The second feature (I think) with MSD or any CD system is the capacitor is a big, fast acting battery that can re-supply the coil with energy very quickly.

All that being said I have energy going in from some controlled source like and MSD, it then collapses a field and a spark happens. Is anyone making a coil that can more effectively make use of this energy? Better wire, better cooling, two inner coils, go fast paint etc?

You have a good handle on what's happening, and as to the coils....well I tore apart a points coil long time ago and found a very crude iron core in there, the thing was built like a real POS inside....

vs the much higher magnetic efficiency of the HEI style core, which is what's known as a E/I lamination setup....2 parts to each steel lamination, the E and the open ends are capped by a I, and so they are alternately stacked as with any other decent transformer....the outer legs of the E pick up the extra, otherwise 'wasted' magnetic field....

the only thing more efficient yet is called a Torroid, but not used for much except car audio that I have seen, in a car that is....

THEN, the audio guys play with the iron composition, entirely another story....