Ashton, NGK offer an 8 series copper plug, I've ran this plug on my s13.
Basically, if you didn't have spark blow-out before and are not going to insane RPM, I would use a Mallory Single Channel CDI box, as you can get one for like 150. If you begin to blow out, these have a very good re-sale value as all the V8 guys want them.
Ben,
You shouldn't try to get too deep into this technology, because you don't have a complete grasp of the situation. The CDI will basically increase the voltage from 12V to somewhere in the neighborhood of 500. The current draw in the system is based on the resistance of the plug, and the resistance and inductance of the coil. The CDI systems use a lower turns ratio coil because this offers a lower inductance. Inductance in a fast system is basically a current choke, because the current passing through it is L*di/dt=V. If you apply 600 volts and close a switch to send current into the coil and 600v is constant and L is large, di (change in current) is smaller.
The energy storage in an inductor is 1/2 L*I^2 (unit is Joules). I term grows at an exponential rate compare to inductance (turns ratio). So basically you use a large voltage to cause a massive inrush of current and discharge this massive increase in energy across the spark plug.
This extra energy is basically an arc that travels from the tip of the electrode to the ground strap on the spark plug. Copper will not last nearly as long as some rare element such as platinum or iridium. However copper plugs are fvcking cheap as sh1t. I replace them on boosted cars every oil change.
Basically, if you didn't have spark blow-out before and are not going to insane RPM, I would use a Mallory Single Channel CDI box, as you can get one for like 150. If you begin to blow out, these have a very good re-sale value as all the V8 guys want them.
Ben,
You shouldn't try to get too deep into this technology, because you don't have a complete grasp of the situation. The CDI will basically increase the voltage from 12V to somewhere in the neighborhood of 500. The current draw in the system is based on the resistance of the plug, and the resistance and inductance of the coil. The CDI systems use a lower turns ratio coil because this offers a lower inductance. Inductance in a fast system is basically a current choke, because the current passing through it is L*di/dt=V. If you apply 600 volts and close a switch to send current into the coil and 600v is constant and L is large, di (change in current) is smaller.
The energy storage in an inductor is 1/2 L*I^2 (unit is Joules). I term grows at an exponential rate compare to inductance (turns ratio). So basically you use a large voltage to cause a massive inrush of current and discharge this massive increase in energy across the spark plug.
This extra energy is basically an arc that travels from the tip of the electrode to the ground strap on the spark plug. Copper will not last nearly as long as some rare element such as platinum or iridium. However copper plugs are fvcking cheap as sh1t. I replace them on boosted cars every oil change.
Be the first to like this post.
Originally Posted by danmartin 
Back to top
