The Tunnel Ram 12V is a new patented intake for the 89-98 Dodge Cummins 12V diesel engine. Proudly made in the USA from aircraft quality billet aluminum and pressure tested to over 200psi, The Tunnel Ram is able to withstand high boost pressures much better than the stock cast plate. It’s unique patented design increases the airflow into the head, which is a known choke point, and distributes the air charge more uniformly between cylinders. What does that mean to you? Faster spool-up for your turbo, lower EGTs (especially in cylinders 1, 5 & 6 which are prone to run hot) and better MPGs.