Diesel Power Source Compound Turbo Kit Stage 4.5 S363/68/12 with Ball Bearing - DCT0199

The Diesel Power Source® Add-a-Turbo Kit is an emissions-compatible compound turbo upgrade for 2007.5–2018 Dodge Ram 2500 and 3500 trucks with the 6.7L Cummins engine. This kit adds a large S475 atmospheric turbo to your existing factory HE351VE turbocharger, creating a twin turbo system that delivers 250–400°F lower EGTs, up to 2.5x more airflow, and 22–26% more horsepower while retaining your factory exhaust brake, EGR, and DPF. It keeps your stock turbo and manifold in place, meaning compound turbo performance without removing any factory emissions equipment. It spools like stock at low RPM, then the S475 atmospheric turbo delivers massive airflow as load increases, making it the cleanest, most OEM-like compound upgrade for the 6.7 Cummins. The kit is designed to work with or without factory emissions equipment intact. It routes all exhaust through the DPS cast hot pipe from the stock turbo to the S475 atmospheric turbo, then out through the included 4\" two-piece downpipe that clamps to the factory exhaust. No cutting, no fabrication, and no emissions components need to be removed or modified. For trucks that are already deleted, this kit works equally well. Diesel Power Source® is pursuing CARB certification for this kit, but it does not yet have a CARB exemption. Your factory HE351VE turbocharger becomes the high-pressure turbo in a compound system. The added S475 atmospheric turbo compresses air first, then feeds that pre-compressed air to your stock turbo, which compresses it again to the final boost pressure. This two-stage compression delivers air that is over 100°F cooler than the stock turbo alone at the same boost level, with boost-to-drive pressure ratios approaching 1:1. Because your factory turbo handles the initial spool at low RPM, throttle response feels identical to stock. As RPM and load increase, the S475 picks up the airflow load and the compound effect kicks in, delivering dramatically more air, lower EGTs, and stronger pulling power across the entire RPM range.