Trick Flow® High Port® 225 cylinder heads are specifically designed for large cubic inch small block Ford engines as well as engines with high-boost superchargers or turbos, big shot nitrous oxide systems, and other mega-power combinations. They feature unique valve spacing, .750" raised exhaust runners, extra strong castings and thick decks for additional rigidity and gasket integrity, superior cooling characteristics, and most importantly, excellent airflow. Top-of-the-line CNC Competition Ported runners with a high resolution surface finish provide maximum airflow and power over the entire rpm range. The entry into the intake runner has been reshaped to help seal the area along the port roof and thicker port walls increase strength and provide additional material for porting. Plus, interlocking ductile iron seats are used to handle the stresses of high heat, high horsepower applications. Other features include fully CNC-profiled combustion chambers with port-to-valve seat blending (bowl blending) and raised valve cover rails.