An induction system for an internal combustion engine, having a combustion chamber and an intake port in periodic communication with the combustion chamber, includes an intake tube having a lower trumpet (41) and an upper trumpet (42), each having an upper end, a lower end and a length; a transition section (43) extending between the upper end of the lower trumpet and the lower end of the upper trumpet; wherein the lower trumpet is connectable at its lower end to the intake port (22) of an engine and has an inner transition diameter (48) proximal its upper end, and wherein the upper trumpet has an inner expansion diameter (55) that is between about 68 percent and 217 percent greater than the transition diameter.