1710 cubic inch (26 litres) V12 supercharged engine, 1200 HP used in Kittyhawks (P-40s) and Lightnings (P-38s). This engine came from Lt Walker’s P-40 Kittyhawk of the 33rd Pursuit Sqdn. destroyed on the 19 February 1942 during the first raids on Darwin. This Squadron was virtually wiped out in that attack, losing four pilots killed, including the squadron CO Major Floyd Pell.
The engine was buried in a bomb crater and unearthed in 1955 when the Darwin runway was upgraded to its present standard.
More technical information about the Allison V-1710 Engine can be found on Wikipedia.