E3 Diamondfire Spark Plugs 31629-78 for Harley-Davidson
12.23 €
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E3 Diamondfire Spark Plugs 31629-78 for Harley-Davidson
12.23 €
- For Sportster XL, XLCH and XLS 1000
- OEM 31629-78
- Spark plug E3.32
- Sold per unit
- The unique E3 ground electrode incorporates the combined benefits of several popular performance spark plug types, as well as new science based on years of spark plug research. The three key performance components that determine how the E3 DiamondFIRE configuration performs are:
- Open Ground Electrode Design This mimics surface-gapped spark plugs like the type used in rotary engines, directing the flame kernel to the piston more directly than traditional J-wire designs. This design reduces travel time from the spark zone to the chamber containing the compressed gases. The open section at the top of the electrode prevents the creation of the donut-shaped flame kernel known from standard spark plugs. Given the short amount of time available to initiate combustion, the faster you can direct the flame to the area above the piston, the better the combustion.
- Forward Projection in the Spark Zone With set-back plug designs, the generated spark is located against the top of the combustion chamber surface. The E3 ground electrode is designed to project further forward into the combustion chamber. This brings the spark zone closer to areas of likely good air-fuel mixing. The outward projection also creates beneficial "microaerodynamics" within the spark zone. Since the initial combustion wave exits the spark area at supersonic speeds, the raised edge of the E3 electrode provides a sort of stack effect as the next air-fuel mixture enters the spark zone.
- Edge-to-Edge Spark Discharge The strongest part of the E3 electrode design is the forced edge-to-edge spark discharge, which proved to be the best way to direct a spark as it leaves the electrode surface. Since the spark itself occurs only when an avalanche of electrons migrates from the two electrodes (cathode to anode), sharp edges are better for initiating migrations, and accelerated electrons collide within the spark zone.