2003 Dodge Ram Hemi Engine Modification - 21st Century Hop-UP

Swapping heads on a musclecar's small-block or big-block engine has been standard practice for many years. Smaller chamber, bigger ports-more power. But what's it take to do it to a 21st century powerplant? Remember, the engine's functions are controlled by a computer; change something that sends a function out of a given parameter, and the computer is lost. Patriot Performance in Rainbow City, Alabama, has a core-replacement program: you purchase a pair of their CNC-ported heads, they ship them to you, and you send your stock heads back to them. The Stage I heads we received featured the stock valves and springs, five-axis CNC porting, and a five-angle valve job. At .600-inch lift, the intake ports flow 300 cfm, and the exhaust flows 207 cfm at the same .600 inch.

Underdriven pulleys for engines are nothing new. Auto Specialties Performance (ASP) has developed one for our new Hemi. The pulley is 20-percent smaller than the factory unit, but the weight of the pulley is kept to the same spec. This alleviates any misfire codes with the computer, and, according to ASP, delivers 12 additional horses and an amazing 19 lb-ft. of torque. it requires a measly 30 minutes to install, and increases horsepower and torque. Sounds like a no-brainer to us. Just keep in mind, you will need to replace the factory belt with a shorter one.