A torque converter and torque divider includes a prime mover input and a torque converter. Each contact surface defines a plurality of V shaped concentric grooves. The injection section of the extruder die assembly is used to impart flavoring additives into the extrudate mass shortly before expansion, thereby preserving the flavoring characteristics of the additive by minimizing the heat exposure of the flavoring additive. Spacers are used to hold a U-shaped UV lamp in the cavity, provide cushioning of the UV lamp therein, and providing additional sealing so that all air passing through the ionizing unit will be treated. The connecting piece has a constant flow cross section over its entire length when the expansion fold is collapsed.