AFR 210cc LSX Mongoose street cylinder heads offer 298 cfm at .600 in. lift, an incredible 70 cfm increase over the stock casting, creating incredible port velocity and performance. They feature 100 percent CNC-ported chambers, A356 aluminum castings, and high-quality components. These heads are recommended for street, strip, and towing engines operating up to 6,300 rpm's from 346 to 383 cu. in. Structural features like Air Flow Research's trademark 3/4 in. thick head deck, reinforced rocker stud bosses, and thick wall runners provide unparalleled durability. An exclusive combustion chamber design with double quench pad area helps the LS1s generate huge low and mid-lift airflow numbers. Put the ferocity of a mongoose under your hood—AFR 210cc LSX Mongoose street cylinder heads.