1971 to 1972 was a transitional year for t he 429/460 and HP drops significantly.

In order to better know what you have, you need to look at some casting numbers located on the cylinder heads. Cylinder head casting numbers are located on the outside of the heads, along the valve cover mounting rail and between the 3rd & 4th exhaust ports.
  • If your pair of cylinder heads casting numbers are "D0VE-A," "D0VE-C," or "D1VE-AA," then your compression ratio is over 10.5:1 and you have about 325 actual horsepower in good tune. Good quality pump gas required.
  • If your cylinder heads have the casting number "D2VE-AA," then it would be wise to begin looking for a new pair of cylinder heads, as those heads are single year (1972) castings and are awful in a perfomance application (detonation prone).
  • "D3VE-A2A" heads are from the 1973-up carbureted engines and your actual HP will somewhere around or below 300HP if optimally tuned. Regular gas no problem.



Paul