30+ years ago they were desirable and found on the 1967 big block motors...but now unless they have been in time capsule somewhere and are absolutely perfect in every respect needing no machine work there are better alternatives and they come in aluminum.

1986 Dodge Ramcharger 440 2wd, Bracket Racer Under Construction
1998 Ram 2500 QuadCab, new daily driver.
2008 Honda Element
2014 Carry-On 7x14 Cargo Trailer