Increase flow area up to 37% over the stock boost tubes with Banks' huge 3-1/2" boost tubes. Stock Ram tubes are plastic. Banks boost tubes are 3-1/2" constant diameter mandrel bent Aluminized Steel with larger radius bends. More air allows for more fuel which means more horsepower. Are you running the new bad-ass Banks Monster-Ram for the 6.7L Cummins? Banks boost tubes are larger than the factory pipe and designed to work with the stock elbow or new Banks Monster-Ram (3.5" or 4") which will improve airflow, and allow the turbocharger to spool up faster. Banks cold side tubes have 37% greater flow area than stock tubes. Produced from high-quality aluminized steel, the tubes are mandrel bent and constant diameter. This allows for quicker turbo spool. Better flowing intercooler tubes improve retention of boost pressure (increases density) between turbo, intercooler, and intake resulting in maximum horsepower. Our red powder-coat or natural finish stops before the end of the tubes for better grip ensuring our 4- and 5-ply heavy-duty high-temperature silicone couplers hold tight under high-boost conditions. Spring-loaded constant tension clamps maintain a stronger grip to prevent leaks or blown boots.