The Chrysler Big Block began life in 1958 and lived until 1978. Many millions of these engines are still out there and in use. When installed, cylinder head identification is difficult between years and application, except for a few pieces. The 1958-1962 cylinder heads had a 4-bolt valve cover (even the Max Wedge). From 1963-1978, 6-bolt valve cover. Industrial engines had a water port at the end of the head and a 3/4-inch spacer cast into the bottom of the head. This allow for very low compression, thus low heat. All other identification must be made through disassembly or valve cover removal. Most heads from 1958-1966 had small valves and were closed chambered (except special pieces like the Max Wedge or 300J). The rare 1967 pieces were large valve, but closed chambered. From 1968-1978 were large valve, but were an open chamber design.

We have taken most of this information out of the MOPAR Engine Manual, however, some data comes from magazines and other documentation. If you have information to contribute or see any errors, please let us know.

1958 - 1978 MOPAR Cylinder Heads

Performance Cylinder Head Data