Abstract: An ignition coil assembly adapted to be mounted directly in a plug hole of an internal combustion engine. The coil assembly includes a primary coil and a secondary coil. The spool upon which the secondary coil is wound is cylindrical in shape and has ramp structures provided at each end thereof. The ramps decrease voltage concentration between the secondary and primary windings, decrease the voltage gradient along the end wall of the secondary spool, and minimize adverse effects of gaps created during thermal expansion/contraction.

Abstract: An electrical connection between a high voltage terminal and a spark plug head. A case contains a high voltage terminal connected to a high voltage source. A connector portion extends from a bottom portion of the case, which in turn is secured to an insulator boot for attachment to the spark plug. The high voltage terminal has a nipple extending within the connector portion. A barrel shaped coil spring is snapped over the nipple and positively retained thereto. The head of the spark plug is inserted within the connector portion and engages the barrel shaped coil spring. The barrel shape of the coil spring offers a smaller height with an increased working length thereby providing a larger tolerance between the high voltage terminal and the spark plug head.