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E3 Spark Plugs

E3 Spark Plugs

Your Price: $6.50
Retail Price:$9.95
Your Savings:$3.45(35%)
Part Number:1520

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Need help figuring out which plug your vehicle requires
If your a mk3 Toyota driver it's a E3.48
All plugs are sold as each....what does this mean?  If you have a six cylinder car you need to order six.

E3 Advanced DiamondFire Technology

DiamondFire technology is the result of an intensive series of laboratory experiments that measured the power created by a spark plug.  For the most accurate measurement of power…

Advanced Technology Overview

Engineering scientists studied the actual pressure rise from a single combustion event with different style spark plugs. The measurement is called the Indicated Mean Effective Pressure (IMEP).  This value is arrived at by running series of combustion cycles and comparing the values from one spark plug to another, keeping all other parameters (load, rpm, temperature, humidity, etc.) equal.  We focused on maximizing the peak pressure created by our proposed electrode designs.

Double blind tests were run comparing the area under the pressure curve itself (the "work" created) for 500 combustion cycles per spark plug design. We also refined our electrode designs to reduce the Coefficient of Variance (COV) of a series of combustion cycles. We performed this work at our test labs in Atlanta, and then continued the development at Georgia Tech and Michigan State University’s Engine Research Laboratory.

The spark plug electrode design we achieved combines the benefits of three types of known performance plugs, and applies some new science as well.  Our DiamondFire configuration outperformed all other spark plug designs available, including premium offerings from the major manufacturers.

There are three main components that determine how the E3 DiamondFire configuration works:
1]  There is a component that mimics surface gap spark plugs (the type used in rotary engines and others) which directs the flame kernel to the piston (or rotor) more directly, reducing the travel time from the spark zone to the end gases.  This avoids the "doughnut" shaped flame kernel produced by standard plugs, and is achieved by opening the section at the top of the electrode. Given the short time available to get combustion started, the faster you can get the flame to the piston, the better.
2]  With retracted plug designs, the generated spark lies against the combustion chamber wall.  So we designed the electrode to project farther forward into the combustion chamber.  This brings the spark zone closer to areas of probable "good" air/fuel mixture.  The E3 outward projection also creates beneficial "micro-aerodynamics” within the spark zone.  The initial combustion wave leaves the spark area at supersonic speeds above Mach 1, and the elevated edge provides a kind of chimney effect so the next round of air/fuel mixture gets into the spark zone.
3] The strongest part of the E3 electrode design is the forced edge-to-edge spark discharge, which is the best way to get a spark to leave a surface. Our design improves upon the phenomena that drove race car drivers to "cut back" ordinary electrode spark plugs in order to improve the spark discharge.  The spark itself occurs only when an avalanche of electrons migrates from the two electrodes (anode to cathode).  Sharp edges are better at initiating electron migrations, and these accelerated electrons collide with matter inside the spark zone to release additional electrons.  With the DiamondFire design, the whole population of electrons works to create a plasma channel through which the spark current flows more easily.


Some competitive spark plug designs (such as the traditional “J-wire”) actually get in the way of the flame kernel as it travels to the piston head and the fuel/air mixture.  But for the most complete combustion, the maximum amount of spark must reach the fuel/air mixture.  The E3 DiamondFire design is open at the end, so the flame travels directly toward the fuel instead of moving at an angle, or sideways.  Seven years of testing has shown that establishing an edge-to-edge spark significantly improves on antiquated spark plug “flat-to-flat” designs that have been around for 100 years.

The fine wire spark plug was designed to reduce the cost of a platinum or iridium electrode by reducing the amount of material needed.  Because of some design modifications, these plugs from major manufacturers do fire a bit better.  But the E3 DiamondFire design outperforms fine wire plugs by maximizing the exposed edges and spark presentation to the combustion chamber.

Our researchers’ most significant discovery is this:  having two sharp edges firing to each other is more than twice as good as an “edge-to-flat” electrode design.  Sharp edge-to-edge designs force the electrons to form the plasma channel faster and stronger.  The E3 DiamondFire design reduces ignition delay and measurable improves the electrical-to-chemical energy transfer.  The result:  a faster and larger flame kernel, more complete combustion, greater power, and higher fuel efficiency.


The flame kernel is created when the spark ignites air and fuel in the spark zone.  The remainder of the mixture will be ignited by one of the following conditions:  contact with the flame front; increase in cylinder pressure (which is how a Diesel engine works), or an increase in temperature (which is called pre-ignition if it happens too early).  If the flame kernel is small, the remaining mixture can ignite by itself when the pressure and temperatures rise as a natural response to the existence of the flame kernel.
Perfect combustion would result if all the fuel mixture combusted exactly when the piston held a constant volume in the cylinder.  The Otto-cycle engine operates on this principle.  But in reality, there is a delay between spark breakdown, flame kernel growth, and movement of the flame front across the combustion chamber.  Peak pressure within the combustion chamber should occur when the piston is around 20° after top dead center (ATDC).
Just after the instant of spark breakdown in the combustion chamber, there is a developed flame kernel and the remainder of the unburnt air/fuel mixture.  To ignite the residual air/fuel mixture, the engine system increases the temperature of the remaining gases, raises their pressure, and exposes them to a flame.  A larger flame kernel is exponentially effective because it offeres more mechanisms for heat transfer:  The larger “ball” of the flame kernel has more surface area, so conductive heat transfer is greater.  The larger surface area also imparts a greater radiation heat transfer to the unburnt gases.  Finally, a larger flame kernel that expands at a rapid rate creates much more turbulence, which strongly affects convective heat transfer by tumbling and mixing the remaining air/fuel mixture, exposing more of it to radiative heat transfer.  This means that just a slight increase in flame kernel strength can cause a cascading improvement in the combustion process.  By getting the flame process started earlier, the “mass fraction burned” at any given crank angle position away from TDC is improved. The E3 DiamondFire design burns the air and fuel mixture already in the combustion chamber more completely.  Since the exhaust valve opening occurs at a fixed point in the crank’s position, it is very important to get as much of the fuel burned before it is vented off by the exhaust valve.  
By measuring the pressure inside the cylinder while the engine is running, very accurate details of the combustion process can be analyzed.

The graph below plots ignition voltage (yellow line) and cylinder pressure (blue line). The blueline starts to rise as the piston moves upward (all valves closed) starting compression. At the right moment, usually around 28° before Top Dead Center (TDC), the ignition system sends voltage to the spark plug.  There is a lag of a few milliseconds from the time the current is sent to the spark plug and when the spark actually starts combustion.  This is called the ignition delay. Once combustion starts, the pressure rises rapidly and peaks after TDC.  This puts maximum pressure on the piston when the connecting rod is at the best leverage angle to the crankshaft. During the power stroke the combusted gases expand rapidly and push hard on the piston. At a certain point the exhaust valve opens and vents off the pressure in the cylinder, meaning that no more work is done on pushing the piston.  
A cylinder pressure graph reveals some interesting information. First, notice the peak pressure and area under the pressure curve as created by different spark plugs. All the power an engine makes comes from the area under this pressure curve. If a spark plug can create higher average pressure for every combustion cycle, it makes more power.

Power improvements are shown on an engine dyno, but that measurement occurs late in the combustion process.  The most accurate and sophisticated way to measure power is to look at the cylinder pressure over a number of cycles (such as 500 cycles) and compare one modification to another.  Since the flywheel integrates the cycles over time, and the individual pulses of each combustion event are lumped together, subtle improvements are hard to determine. For optimal tuning, major race teams from NASCAR to Formula 1 are now equipping their cars for in-cylinder pressure measurements. E3 engineers pioneered this practice in the mid 1990s.

The following graph shows how the E3 spark plug creates higher pressures in a test engine, compared to a standard spark plug. The higher and more consistent pressure levels directly result in more power and less emissions, while burning less fuel. More fuel is converted to power, driving the piston downward more efficiently.  Less fuel is blown out the exhaust. This is the heart of the substantial performance improvement resulting from the E3 DiamondFire design.
Another important observation is the variation of peak pressure values from one combustion cycle to the next.  Surprisingly, not all combustion cycles make the same power. A well-running engine will still have a 5% drift in pressure values from one power stroke to another. A poor running engine will have 10% or more. This is called “coefficient of variability” and can be seen in the next graph. Some combustion events result in high pressure production, others result in low pressure. The graph shows successive combustion events taken in real time, showing how cycles vary from one another even while the spark plug is firing very well.


The graphs show that the E3 DiamondFire design produces more consistent and higher combustion pressures as an average over successive combustion events. This leads to more power, and helps reduce emissions and improve fuel economy. Pressure traces of this sort show up in every engine we have tested since 1997.

The graph below shows how E3 spark plugs improve pressures over a series of combustion cycles and how this adds up to better power. The blue line was measured over a successive number of power cycles using E3 spark plugs. The pressure peaks are higher and more uniform than the standard spark plug (shown in the blue line). The dotted lines represent an average of the pressure curves. The blue dotted line shows the running average of the E3 spark plug pressure/power production. The dotted red line shows a lower average for the standard spark plug.

E3 researchers have performed this type of analysis and have measured consistent improvement in automotive engines, small two strokes, high revving racing four strokes, etc.  Making the flame front faster and the combustion pressure rise faster always results in more complete combustion and this directly improves engine performance.  

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