Are you looking for big torque and big horsepower number? Our BB Chevy line of medium volume intake runners will provide you with exactly that. The phrase ñ having your cake and eating it toî would certainly be appropriate with their moderately sized intake runners producing tremendous flow figures across the entire lift range (Our CNC 335 flows 410 CFM!). These high flow/high velocity ports provide extreme versatility and fill the needs of many applications. From a max-effort high compression 454 to a 605 CID low rpm marine application, either one of these cylinder heads would be a great choice. These heads would also be ideal in a larger cubic inch ñ Pro-Streetî application with their broad torque range, as well as significant rpm and horsepower capability. These heads will work best with a primary operating range of 3000-7000 rpmÍs (This range is an average and will vary with engine displacement as well as component selection). Both the 325cc and the 335cc come standard with AFRÍs trademark .750î thick head deck, reinforced rocker stud bosses, and are equipped with premium one piece stainless steel 2.300î intake valves and 1.880î exhaust valves. Standard combustion chamber volume is 119ccÍs on our 325 ñAs Castî pieces, while the fully CNC ported 335 version comes with a 121cc chamber. Both are available with an optional 114cc combustion chamber as well. Chevrolet Big Block - 325cc Competition Package Ported Heads, Bare - 121cc Combustion Chambers