The EC PVL Ignition Coil replaces the outdated transistor-type coil from over 50 years ago with modern digital technology. This new PVL digital system offers racers a relatively lightweight, more robust, and more precise product than traditional analog systems. Unlike most digital CDI systems that require a separate power source, this system only needs the integrated magnet in the flywheel.
The new PVL system can be utilized directly on most Briggs Kart Engines or adapted to most Honda/Clone Engines(e.g., Predator, Tillotson, Wildcat, etc.) using a coil bracket.
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The PVL coil is physically larger than most traditional analog transistor coils. The coil must have enough spread of the coil legs to pick up energy from the flywheel magnet and power up the system before the plug is fired, which allows it to make calculations for the ability to adjust the spark timing independent of the magnet position to the coil. The coil’s bigger physical size has no adverse effect on the engine, but you may require a different blower housing to fit the coil on your Honda/Clone. We designed the Tillotson Heavy-Duty Blower Housing to make room for the PVL Coil for your Honda/Clone engines.
The PVL ignition coils have been providing excellent performance on different kart engines for decades. Not only has extensive shock and thermal testing been done during initial development, but decades of track testing and racing have proven the durability and performance of these ignition coils.
How does the PVL output compare to the original analog ignition?
CDI ignitions offer more significant power potential due to the primary coil storing and releasing more energy. The capacitor can store up to 200 volts, which is discharged instantly when the processor signals it to fire. In contrast, the original coil only has the energy generated by the passing magnet, which is much lower. The two coils operate like a step-up transformer, so determining the secondary output voltage involves multiplying the primary coil voltage by the winding ratio of both coils. The primary voltage is significantly higher with the new CDI because of the high voltage stored in the capacitor. This system ultimately provides a higher voltage potential at the spark plug since the increased primary voltage is multiplied by the coil ratio.
The plug will only use the voltage required to jump the gap. This voltage requirement will increase as the pressure inside the cylinder increases or the plug gap increases.
Benefits:
Wide Plug Gap: A wider plug gap can help with a stronger initial burn and flame front for better combustion.
Higher Cylinder Pressure: Engines with high compression and early intake closings can increase cylinder pressure, which creates more resistance in the combustion chamber. The higher voltage of the PVL will help the coil fire through this resistance for better combustion.
Rich Fuel Conditions: Any carburetor tuned for power will be considered rich. Our small engines are no different but can be worse since our small engine carburetors are rich at idle due to the lack of an accelerator pump or additional fuel circuits for low speeds. Instead, idle is compromised for better midrange performance and on/off throttle response at race speeds. This rich condition can make traditional ignition hard to fire through wet conditions, especially under high cylinder pressures. The higher voltage of the PVL helps the plug fire through these conditions.
To get the most from any ignition system, including the PVL digital ignition, we recommend a 028-.034 plug gap and fine-wire iridium, which also allows wider gaps and helps with higher cylinder pressure and rich conditions.
About the company PVL
Many have assumed PVL is a design for a type of flywheel or ignition coil, which has caused confusion when using PVL digital ignitions.
PVL (Probosch-Vogt-Loos Electronic and Elektrotechnik GmbH & Co KG), headquartered in Cadolzburg, Germany, and now owned by Tillotson, has been designing and manufacturing innovative analog and digital ignition systems and other components for the small engine market since 1970.
PVL’s high-performance electronic ignition systems spark various industries. They are found everywhere where ignitions have to function reliably in the most adverse environmental conditions—in lawnmowers, outboard engines, jet skis, motorcycles, and racing go-karts. Many PVL ignition modules are homologated for international karting competitions and have carried drivers to numerous European and World Karting Championships for over 25 years.
Their top-notch ISO 9001-certified manufacturing facility is the perfect match for producing this digital coil. They have the experience, technology, and quality to make a reliable system for today’s 4-cycle kart engines.
PVL Compatible Flywheels
Due to its digital characteristics, the coil’s operation is more complex than the original transistor coil; however, the fundamental theory of operation remains similar. As the flywheel magnet passes by the lamination stacks, energy is transferred up the stacks when the opposing poles pass the legs of the coil, providing the necessary energy to power the electronics and produce the spark. The original coil had a north-south-north pole orientation as the flywheel moved past the coil legs.
The new PVL system features a south-north pole orientation, which is essential for the proper functionality of the coil. Unfortunately, this configuration means the new coil will not work with OEM flywheels or aftermarket flywheels designed for stock analog coils. A common mistake is using the cast aluminum PVL flywheel carried by Dynocams, which was made for the stock analog coils. Most manufacturers explain the compatibility of the flywheel with the PVL digital coil. Our flywheel’s part number is SK300.
This magnet generates the energy needed to power the entire system, including energizing the control module and firing the spark plug.
How the PVL Works
The following is a breakdown of the coil’s operation as the flywheel magnet passes by the coil legs. The magnet passes by the coil from left to right, with the leftmost leg seeing the magnet first.
Number 1—We refer to the leftmost leg as the charging leg. It harnesses energy from the magnet to charge the capacitor (an electronic storage device), which powers the processor and triggers the plug.
The processor is programmed to control ignition timing, determining when to discharge the ignition coil based on the crank position and engine speed (rpm). It can make precise adjustments to the ignition timing, either increasing or decreasing it based on engine speed, to create a timing curve across the coil’s rpm range.
The charging leg of the coil initiates this entire process.
Number 2 - The second leg serves as the primary trigger leg, a reference for firing the ignition coil. For instance, you should set your static ignition timing from the right side of this leg, typically around 30° on our flywheel. The trigger leg enables the processor to determine the duration of one engine revolution and the average engine speed, allowing for adjustments to advance or retard the ignition timing based on the processor’s programming. Altering the flywheel with or without a timing key will modify the starting point for the timing curve. It’s advisable to use the flywheel with a stock timing key.
Number 3 - The third or amplifier leg serves to enhance spark energy. The CDI (capacitive discharge ignition) uses the energy stored in a capacitor to send current to the primary coil, which is stepped up in the secondary coil to produce the high-voltage spark. This third leg gives the system a secondary current source that helps amplify the capacitor’s voltage at the time of the spark and increases the spark’s duration. When the timing is set within a specific range, as in our particular case, the spark duration is amplified because of this extra energy. So much so that its spark duration is actually longer than that of its transistor counterpart in certain areas of the speed curves; this increased energy associated with the third leg’s position is only affected by what is programmed into the processor and is independent of the flywheel’s position at the crank. PVL has optimized this for us so the system offers the more significant voltage potential associated with the CDI-type ignition and has the longer spark duration typically only seen by transistor-type coils.
Number 4 - The fourth leg (furthest to the right) is the secondary trigger leg. This hardware trigger fires the coil before the processor can operate below 1000 rpm, and it is used only during start-up. At engine speeds above 1000 rpm, the processor takes over, using the primary or second leg for trigger information. The hardware timing is set at approximately 10 degrees at the standard keyway position for easier starting. Additionally, there is an extra 20 degrees of advance before the engine reaches idle speed, totaling 30 degrees of advance based on our SK300. Adjusting the flywheel with or without a timing key will change the starting location for the timing curve, so it’s best to use the flywheel with a stock timing key.
Installing the PVL Ignition
1. Follow our instructions for installing and troubleshooting our SK300 PVL Flywheel ( Instructions come with the flywheel and found on our website)
2. For Honda/Clone Engines, use the coil bracket provided with our SK200 or other aftermarket compatible flywheels, or if you have bought a bracket separately. Torque bracket to 7ft-lbs
3. Snug the PVL onto the bracket and adjust the coil gap to .040”. Then, tighten the PVL bolts to 40in-lbs
4. Set plug gap between .028-.034”
PVL Ignition Timing
Optimal ignition depends on many factors, including compression ratios, cam timing, combustion chamber & piston design, and fuel volatility. It can also depend on ambient temperature(less timing) and humidity/dew point(more timing). Tuning for optimal ignition timing requires a dyno. We recommend starting with a stock key or between 28-32° ignition timing. You should have a readout of where peak torque was made; this will be your tuning reference. Ignition timing can be added or advanced until you see a drop in peak torque. From here, we suggest backing off at least 2 degrees to prevent detonation. One or two degrees less will not hurt performance, but exceeding one or two degrees more can lead to excessive wear and engine failures, usually crank, rod, or piston failures.
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