Are you running the new bad-ass Banks Monster-Ram for the 6.7L Cummins? Banks boost tube is 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 tube has up to 67% percent greater flow area than stock tube. Produced from high-quality aluminized steel, our tubes are mandrel bent for constant diameter. This increases performance by allowing quicker turbo spool. Better flowing intercooler tubes improve retention of boost pressure (increases density) between turbo, intercooler, and intake resulting in maximum horsepower. Our natural finish tubes give you the freedom to paint or powder-coat to your color of choice. The bead-rolled ends allow 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. This boost tube is designed for serious horsepower.