Daytona Twin Tec Ignition modulesFeatures two advance curve families that are adjustable to accommodate stock and modified engines Selectable multi spark mode for quick starting and smooth cruising Four rotary switches for mode select, timing adjustments, advance slope and rpm limit (in 100 rpm steps) Coil outputs protected against short circuits '99 '06 Twin cam models requires coils with less than 1 ohm primary resistance and low resistance spiral core or carbon core suppression