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LS Coil Ignition System

     You know the Ford folks did a really good job with the new Modular Engine and it's Electronic Ignition System.  All in all, it works very well, is very compact and reliable.  For 70% of all users, it works and is all they will ever need.  For the next 15 %, those that run higher performance engines, mainly those with a Supercharger or Turbocharger that creates positive pressure in the intake manifold, or Boost as most like to call it, the stock system is not enough.  For these people, they more spark them the stock components can deliver.  There are several additional options that might work well for this group, one would be aftermarket Coils.  These are simply Coils with a higher turns ratio.  The Turns ratio is the difference between the primary and secondary side of the Coil.  Just a quick reminder, the turns ratio of say 55:1 would mean the for every winding on the primary side of the Coil, there are 55 windings on the secondary side.  This translates into a 12 volt feed of the primary coil producing 660 volts on the secondary side.  Simply, 12(volt) x 55= 660 volts.  On a Coil, the two sides, the Primary and Secondary, never touch, the coils are separate and the voltage is induced, meaning put two Coils next to each other and the one will affect the other.  In this case, with a 55;1 ratio, you see how it effects the other Coil, by inducing a much stronger voltage into it.  Want more voltage, simply add more windings to the secondary Coil.  You have probably seen real large coils like the Accel Super Coil?  This is a perfect example.  Our problem on the Modular Engine, is we do not have the room to add many windings to that secondary side.  Why?  Look where the Coil is located….Down and inside the relatively small hole in the Valve Covers.  This physically limits our size and thus our secondary Voltage. 

     Let's back up one moment….and look at some real advantages of the Modular Ignition System.   First and foremost is the fact that we have the Coil located right on top of the Plug.  This means we have no Plug wire to worry about.  Why is that an issue?  Plug wires have to carry that secondary voltage from the Coil to the Plug, on some engines and certain cylinders that can be a pretty long distance.  The wires cannot be made of copper, like a ordinary primary wire, that would supply the Coil with voltage.  This copper core would need way to much insulation to keep the plug wire from arching, plus copper would not form around the bends that well nor would it work very well with both the radio and various computer parts because of radio interference issues.  Typically they use a graffite core or some compact form of it to pass the voltage. This has a high resistance, meaning it does not want to pass along that voltage very easily, so you lose voltage from the Coil to the Plug.  The core is also easily damaged, and the Plug wires are constantly breaking down from the high voltage they pass.  This means they do not last very long, especially exposed to the heat of the engine and the vibration of running.  So, the shorter the distance from the Coil to the Plug the less energy we lose, and if you can eliminate the Plug wire altogether, that’s that best scenario available.  Remember we have COIL ON PLUG while the Chevy folks and there LS series engines have COIL NEAR PLUG.  There is a difference, with COIL ON PLUG, there is no plug wire and the Coil literally Plugs into the spark plug.  With COIL NEAR PLUG, the Coil is very close to the Plug, but still connected by a spark Plug wire.

     Another advantage of having a Coil for every cylinder is something called Saturation.  The Coil is really just like a capacitor, and capacitors store energy.  The Coil takes in the primary voltage and induces a secondary voltage that is much higher than the primary voltage, its true value dependent on the turn ratio of that Coil.  While this transformation from primary to secondary voltage happens very fast, you have to remember the engine is also running very fast.  Now the Coil stores this voltage or charge until the primary voltage source is broken, then the field collapses and the secondary Coil expels it's charge, this is what is sent to the spark plug.  On a Points Type Ignition System, the opening of those points by the distributor shaft, is what interrupts the primary voltage source, this causes the magnetic field to collapse and allows the secondary to send it's charge onward.  If you have one coil for a V-8 engine, that Coil has to charge and discharge 8 times for every 2 revolutions.  The time the Coil has to fully charge the secondary side, is Saturation.  You might have also heard the term Dwell:  This is the same thing, the amount of time the Coil has to charge, but expressed in degrees of engine rotation.  Maximum Dwell for a 4-cycle engine would be 90 degrees of engine rotation, 360 x 2 /8=90.  That would be under the best circumstance, 90° of rotation to charge the coil, but due to mechanical conditions like gear back-lash, point opening, rotor to point contact, plus many more, the actual time or dwell is much less, generally closer to 55-60°.  Still, 55-60° doesn't sound so bad, but look at the engine while running and it looks less convincing.  1000RPM looks like this:  distributor turn 500 times in 60 second or 8.33 times a second.  This means the Coil has fully charge and discharge 66.66 times/second.  While that is a lot, modern electronics can handle that pretty well, the problem get much tougher at 4000RPM or 7500 RPM.  At 7500 RPM the Coil now has to charge and discharge 499.99 times in just one second!  While the Coil was fully saturated at 1000 RPM, it starts loosing efficiency the higher we go, till at 7500 RPM, your lucky to get 50% saturation.  So you lose voltage, and time for the spark to take place, which causes miss-fires and poor performance. 

    Having 8 Coils is a big deal….You can see how it helps with Coil voltage and saturation.  That Coil for cylinder 2 only has to worry about cylinder 2, while before the Coil had cylinders 1,2,3,4,5,6,7 &8 to worry about.  Combine the lack of a plug wire and all it's losses, with each cylinder having its own Coil, and you really start seeing some significant gains.  For not only does the Coil have less energy as RPM goes up, but as Cylinder pressure builds, it makes it harder for the spark plug to fire its spark.  How?  Resistance.  At atmospheric, the resistance against the spark plug to fire is so much, but as cylinder pressure increase it become increasingly harder and harder to fire.  The normal automotive engine produces compression with each time the piston is raised during the compression stroke.  How much depends on your engine's compression ratio, generally, with about 9:1 CR,  you'll have 145-160 Lbs pressure in a cylinder.  Add to that a higher static compression ration like 12:1, or higher, and or the induction of Boost Pressure and those number climb much higher.  If you double Atmospheric Pressure (1ATM) to 2 ATM or 14.8 Lbs Boost, the cylinder pressure doubles, take the boost to 29.6 lbs and it triples.  On many high horsepower racing engines, the cylinder pressure can be extraordinarily high.  Those in the Tractor Pulling sport run compound turbochargers and boost pressures many times exceed 200 lbs pressure!  Which will come in handy for another project we have going, that takes three (3) Turbochargers, two (2) small feeding one (1) large Turbo in a compound boost manner.

    So what do we know?  We know the 8-COIL ON PLUG arrangement the modular engines have is a very good system, and the only real limiter is the physical size of the coils, which limit output voltage.  Back to those next 15% with added performance.  We can go to aftermarket coils and expect about 8-10% more spark energy, and combine that with a Kenny Bell Boost-A-Spark for additional spark energy.  The Kenny bell approach is a very common one used by both Ford and Chevrolet camps.  Basically, the Boost-A-Spark is a voltage booster, since it allows you to supply the primary side of the Coils with more voltage, that means the secondary side will have a voltage increase as well.  At maximum, you can get 18-20 volts from the Boost-A-Spark, this subtle increase allows most to get by, giving the plug just enough extra spark to jump the gap and ignite the air/fuel mixture.  It you don't have the energy to jump that gap on the spark plug, what do you do?  Add the coils and Boost-A-Spark first, then your only option is to decrease the gap on the spark plug itself.  Bring the distance from the recommended 0.032" to 0.035" down to 0.025" or until your dead cylinder fires again.  But this makes the spark it does expel very small and week, which will effect performance and how much boost pressure you can run.  Like I stated, 15% of the performance guys will get by with this approach, but now were left with the last 15% of performance enthusiast that are out of options, or at least have to settle for less than optimal ignition performance.

     This is where my new ignition system will come into play.  Don't get me wrong, anyone can use this system on the their modular engine, just this last 15% would have no choice but to run another ignition system other then the Ford EDIS system, on their car.  Now where down to physical coil limitations and efficiency.  The COIL ON PLUG system Ford came out with has just hit the wall, with regard to a performance ignition system.  For those that do run Superchargers or Turbochargers, there is an awful term they hate to here, it's call Blow Out or spark plug blow out.  The electrical system is no longer capable of keeping up with the engines performance, and the spark plug simply will not ignite the fuel/air mixture any more.  Basically, you have a dead cylinder or worse with this type of deficiency, you have multiple dead cylinders.  Only igniting as cylinder pressure drops back down beyond the threshold of blow out.  This not only kills power but limits performance, remind yourself were talking about those that run wear the other 85% will not, at the very top, some at the tip of the performance threshold of the modular platform.  These guys spend huge amounts of money on parts, engines, high octane fuel and the cars themselves.  They travel hundreds of miles to get to a track to compete, and today that equates into some major money in and of itself.  Others are street cars that have to run on premium fuel, they have to control the ignition system to make power but avoid pre-ignition knock, which can destroy an engine in a very short time.  Both groups do not want or can afford costly engine damage or down time…This is where our ignition system comes in.

     The LS Engine has a COIL NEER PLUG system, so the Coil while being very close to the spark plug, is not down inside the valve cover.  This allows the LS Coils to be much larger in terms of Coil ratio then the modular Coils.  That means they can deliver a stronger, higher secondary voltage to the spark plug, which in turn makes a larger more powerful spark to ignite the air/fuel mixture in the cylinder, giving increased performance.  Also, because of the shape, the LS Coils are more efficient then modular Coils, which allows them to make more power with less energy, again something that increases performance.

     The trick has always been how to get the LS Coils to work on the modular platform.  You see the two companies use very different technology to do the same task.  The Ford camp uses a positive lead to energize the Coils and a negative lead to control the firing, while the Chevy camp uses a negative lead to ground the Coil and a positive lead to energize it, and another negative lead to control the Coil.  The systems are at opposite spectrums of the ignition universe.  That plus the Ford computer controls the Coil firing sequence, with a very low current circuit.  Get it wrong and the only thing that will ignite is your control box, as many have found out.  While it has taken us some time, we have finally found a way to both control and energize the LS Coils with ah Ford EDIS System!  Our system comes pre-wired, pre-terminated and fully built with its own control box.  There was a lot of thought that went into the new Ignition system.  We wanted a system that was high performance, dependable, easy to use, adjustable, and most of all, easy to install.

     There are at least 4 different LS based Coils you can use, we chose the Coil that we thought would work best in this environment.  It has almost 4 times the spark energy of a Ford COIL ON PLUG Coil, is well designed, weather proof, and has a built in heat sink to control internal temperatures.  This is important, since as temperatures go up, resistance goes up, which makes power output go down.  We also decided to make the system compatible with the Kenny Bell, Boos A spark.  This will allow users to customize the system to their needs, expand the output as performance dictates and allow another level of flexibility.  We also wanted the system to be not only well built but good looking as well.  The main control box is a custom aluminum piece that houses all the internal components, and mounts the Boost A Spark, plus has all wiring harnesses attached.  Speaking of which, we wanted the wiring to be both professional and easy.  We got a major harness manufacturer to build us a great piece.  The system comes with factory terminals for ease of installation and dependability.  We used the same type wire the OEM uses, for long life and dependable service.  You simply un-plug the connectors at the Coils, and plug our harness in, it's that simple and easy.  Beyond that, you simply have to hook-up the main supply lines to the battery and the new terminals to the LS Coils. 

     The system involves no…I repeat no cutting of wires, and you can at any time simply un-plug our ignition system and plug back into your old EDIS COIL ON PLUG system.  We spent the time to make it right, we used the best parts, professional, factory like connectors, and all the care anyone could muster.  The billet aluminum Coil mounting brackets attach to the valve covers with quality Stainless Steel hardware and top quality LS Coils.  You can polish out the brackets or anodize them for a custom look for those with show car taste.  We made sure the harness assemblies are top notch, with high quality wire, connectors that are color coded and easy to install.  The control box features strain relief type harness connectors, a mount for the optional boost A Spark control box and both supply power and control LED indicator lights.  So, at a glance, you can verify the stasis of the supply feed and control circuitry.  You have some variance in where you mount the control box, but generally there is enough leeway to mount it on the rear firewall or drivers side inter fender panel.  Once we get enough testing on the prototype unit we have pictured here, we can start taking orders.


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