Don't let their size fool you—AFR Magnum 305cc "as-cast" heads with a CNC bowl blend will provide you with flow numbers that most medium-sized heads, and some larger, can only dream about. This line was designed to optimize low and mid-lift airflow, while still generating impressive peak figures. Their application should be focused on smaller cu. in. Chevy big blocks (396-502) with a primary operating range of 2,500-6,800 rpm (this range is an average and will vary with engine displacement, as well as component selection). AFR 305cc Magnum BBC heads should also be given strong consideration in larger street-driven or marine applications up to 555 c.i.d., where low-rpm power and drivability are factors. These cylinder heads would be a great choice if you're looking for big torque and strong low-rpm performance and still have good rpm capabilities. The heads come standard with AFR's trademark 3/4 in. thick head deck, reinforced rocker stud bosses, and premium one-piece stainless steel 2.250 in. intake valves and 1.880 in. exhaust valves. Standard combustion chamber volume is 119cc. These heads are available with an optional 114cc combustion chamber as well.

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