A corona coupling system with a plurality of corona coupling unit blocks, individually snapped on spark plug wires and coil wires, interconnected by wire for corona coupling distribution between the spark plug and coil wires. The blocks are interconnected by two generally parallel, insulated wires clamped in place running through each two-piece block by a stamped conductive metal plate having formed-down corners biting into and through insulation on the block interconnecting wires as plastic top and bottom parts of each block are pressed and sonically welded together. The stamped conductive metal plate is formed with a downward longitudinally extended ridge positioned in the blocks so that the bottom edge rests against and along the insulation of the wire on which each block is mounted.