Stainless Steel Cummins Exhaust manifold T-3 12 ValveSled Puller Stainless Diesel exhaust manifolds come with 2 ports drilled and tapped for EGT & Drive. Our Stainless exhaust mainfolds are made with shell molding its a super smooth inside and out casting technology that has superior flow over and above the old type 60 grit sand paper like looking and filling casting that all the other exhaust manifolds are made from.The manifolds have 3/4 inch thick center section [for those of you that like to custom port to your specs] Thick wall casting to keep heat in and the inside runner sizing is 1.650 inchs all the way to the center outlet for high flow. The stainless manifolds make large turbos more drive-able, improves spool-up several hundred RPM's. Improves horsepower and widens powerband. Increased economy, when installed with same mods. Excellent fit & finish! Has superior flow over the competors. Has large 1.65" ports, full length to collector foot. Smooth runners with extra porting room.T-3 Stainless Diesel manifold is in the same location as the OEM manifold. It's a direct factory replacement for your Dodge Cummins truck.