These are the factory C8OE cylinder head castings for 302-2V engines with 58cc chambers professionally machined by L & R Automotive Supply Company--perfect for our flat-top pistons. These heads have a fresh three-angle valve job with Speed Pro valves and Crane springs, retainers, and keepers. Spring pressure is matched to the cam profile. These are actually Windsor foundry castings, not the Cleveland iron we usually see. Look to Power Heads for CNC-ported iron heads for under $700. Opt for 351W castings from Power Heads and make even more power.