What engines were in P-51 mustang?

* Allison V-1710: The Allison V-1710 engine was used in the early models of the P-51 Mustang, including the P-51A, P-51B, and P-51C. This engine was a liquid-cooled V-12 engine that produced 1,150 horsepower.

* Packard V-1650: The Packard V-1650 engine was used in the later models of the P-51 Mustang, including the P-51D, P-51H, and P-51K. This engine was a liquid-cooled V-12 engine that produced 2,000 horsepower.

* Rolls-Royce Merlin: The Rolls-Royce Merlin engine was used in the P-51B/C Mustang Mk I and the P-51D Mustang Mk IV and Mk XII. The Merlin 61 engine produced 1,490 horsepower for take-off, and in later models up to 1,720 horsepower was available in emergencies by adjustment of the automatic boost regulator mechanism (the "emergency boost" setting, used only once per sortie to avoid engine wear).