Chevy fourth generation aluminum big-block head is readily i.d. 'ed by "bow tie" emblem and new square exhaust ports that exit ¾ inch higher than previous D-port design. You'll have to drill new ...

The Chevrolet small-block engine was a brilliant piece of engineering, attested by the fact that well over 100,000,000 have been built. However the first generation was not as oil-tight as later ...